Help-Where's my Oil Going? [Archive] - Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum

: Help-Where's my Oil Going?


quag421
01-17-2009, 07:21 PM
Hope someone can help, searched the threads but didn't see my issue. Bought a used (Certified) 06 Denali. To be honest we have had it in three times in 3 months, mostly little crap.

I haven't changed the oil yet, but checked it before a trip over Christmas and needed to add a quart. Just thought the dealer never topped off so didn't think much about it. Checked at the end of the trip, needed another 1/2 quart. And just added another 1/2 quart today.

Call me crazy but I shouldn't have to be adding 2 quarts between oil changes with 34K on it. No leaks that I can find underneith and nothing on the garage floor. Not seeing any smoke or signs of burning oil. Engine is running fine, and not throwing any codes.

We had a 04 Envoy with the I6 and over 90K when I traded it in. Never once did I add oil btwn oil changes. Getting a little concerned we my have a problem child.

Any ideas?:confused:

Super 88
01-17-2009, 08:41 PM
I would say you definitely have a problem somewhere. As you probably already know - oil can only disappear in one of two way. Either the engine can burn it by the oil getting past the rings and/or valves, or it is leaking somewhere.

Sometimes an engine CAN burn oil and it will not be enough that you can see it while you are driving.

Something you could try is - change the oil and use a different brand. I have heard (but never experienced) that occasionally a different brand of oil will cause it to use oil. I'm not sure I buy it - but that's what I've heard, and like I said I've never seen that happen in any of my vehicles.

You can try complaining to the dealership, but they are probably going to tell you nothing is wrong.

I usually go about 7K - 9K miles between changes and have never had to add oil - with the exception of when the engine was new I had to add one quart.

91RS
01-17-2009, 09:09 PM
You bought a certified car, so that means it shouldn't have any problems like that. Take it back and have them look at it, besides you're probably still under warranty anyway (or at least close enough where they could good-will the repair).

n0kfb
01-18-2009, 11:28 AM
I'd bet that this level of oil consumption is considered normal by GM.

To fix this you need a lot of engine work. Cost would no doubt be thousands of dollars, and the problem might not be fixed. Even if you use synthetic oil at $5 per quart, $1000 will buy 200 quarts of oil.

You don't say in your post, but just exactly how much oil is your truck using? Are you using synthetic oil? If so stop using synthetic. Also, changing brands might help this issue as well.

In any case, I don't think GM will do anything for you.

Try the things listed above. Keep us posted.

-- Dan Meyer :coffee

91RS
01-18-2009, 11:49 AM
The accepted usage is 1 qt. in 2000 miles. Doesn't matter though, it's a certified car and shouldn't have a problem like that.

rrufast
01-18-2009, 02:36 PM
Could be leaking around valve cover gasket? Mine has started using quite a bit.. I just add it.. until I can pinpoint whre eit's coming from. I don't think it's blow by (ring failure) because it does not smoke at all.. on startup or any other time. I have noticed a little seepage near the CPS or whatever it's called.

n0kfb
01-18-2009, 04:57 PM
The accepted usage is 1 qt. in 2000 miles. Doesn't matter though, it's a certified car and shouldn't have a problem like that.

I don't see on the GM certified web page that they actually verify the oil consumption. See http://www.gmcertified.com/certified/whatis/index.jsp?deep=inspection#view_full

Second, exactly what is the rate of oil consumption here?

-- Dan Meyer :coffee

quag421
01-18-2009, 11:29 PM
I've put about 2 quarts in for about 2-3000 miles. I have not changed since I bought, but assumed that the dealer used regular 5W30 not syn. Owners Manual calls for regular. Mostly after highway driving. Figured I'd call the dealer in the am and see what they say. Really disappointed however, have had a bunch of crap with this one. And I would would have thought a Denali would be better built then a base Envoy XL. Had no problems with that.

ltdakheel
01-19-2009, 09:11 AM
check the POSTIVE CRANK VENTILATION SYSTEM PCV its maybe the engine not cooled by air i,m mean from inside this valve could make the oil boiling if its defected or check the engine oil cooler if you have my biggest idea is your oil is over temp

Super 88
01-19-2009, 11:43 AM
check the POSTIVE CRANK VENTILATION SYSTEM PCV its maybe the engine not cooled by air i,m mean from inside this valve could make the oil boiling if its defected or check the engine oil cooler if you have my biggest idea is your oil is over temp

Just one problem with your theory. The I6 engine does NOT have a PCV valve.

http://forums.trailvoy.com/showthread.php?t=27420&highlight=pcv

quag421
01-19-2009, 12:57 PM
First off this is a 5.3 not the I6, second, I would assume if the oil is over heating the engine would be as well? That does not seem to be a problem.

I did call the dealer today. I will take it in and they want to change the oil and put a dye in then check every 1000 miles, however he did say they have a bulletin that says the motor can use up to two quarts between oil changes and still be normal. That seems like a lot to me and from this forum I don't see anyone else saying they have this issue, particularly on a motor with 34K on it.

I am certainly not an expert, would like to know if anyone else has experianced this on a 5.3.

Super 88
01-19-2009, 02:21 PM
First off this is a 5.3 not the I6,

Uh then you might want to change the info on your profile. In your first post, you did not mention it was a V8 instead of the I6.

ltdakheel
01-19-2009, 03:42 PM
the I6 does have the PCV check this picture its should i haveit before on V6 4.3L 262 i dig more for hole system and parts that just for now
number 503 PCV hose form crank case

Super 88
01-19-2009, 04:56 PM
the I6 does have the PCV check this picture its should i haveit before on V6 4.3L 262 i dig more for hole system and parts that just for now
number 503 PCV hose form crank case

Read my post very carefully. I said it doesn't have a PCV VALVE! Yes there is a hose, but not a serviceable valve like many cars have.

This is also mentioned in the link I posted to the other thread.

What you had before in a V6 4.3 engine really doesn't have any bearing with what our engines have. Completely different animals!

quag421
01-20-2009, 08:05 AM
Uh then you might want to change the info on your profile. In your first post, you did not mention it was a V8 instead of the I6.

Sorry, had an 04 with an I6 when I signed up to this post. Traded it for an 06 Denali in October. I will update my profile.

etperez22
03-22-2009, 05:02 AM
purchased on 06 denali as well, had it for a month now and have not changed the oil. I checked recently and it is just above the lower XXX marks on the dip stick.. I would figure that the dealer would change the oil and fill to the top of the XXX marks..

did you find out what is going on with your Denali and what did the dealer do to fix? or if they even fixed??

markarock
03-22-2009, 09:50 AM
I bought a used 5.3L TB in December with 51k. I now have about 55k on it, meaning I have driven 4000 miles or so. The oil had been changed by the dealer, and it was full when I picked it up.

I have now put two quarts into it. The oil life monitor says 29%.

Previously I had an I6 03 Envoy, and went 10k without putting in a quart. So, I"m spoiled, as are you.

BUT, until I had an I6, I would have thought that one quart every 2000 miles was perfectly acceptable. That is about what I get in my 3.8L Bonneville.

My tentative conclusion is that a quart every 2k is "normal" for the 5.3L.

My other conclusion is that if I am replacing 40% of my oil before the oil life monitor says change the oil, then I can go 40% longer before I change my oil. I'll reset the monitor but not change the oil, and then change it when I get down to 60%, by which time I'm sure I'll have added yet another quart.

Just my thinking.

Super 88
03-23-2009, 01:02 PM
My other conclusion is that if I am replacing 40% of my oil before the oil life monitor says change the oil, then I can go 40% longer before I change my oil. I'll reset the monitor but not change the oil, and then change it when I get down to 60%, by which time I'm sure I'll have added yet another quart.

Just my thinking.

I would rethink your thoughts! :D

Going on your theory, you would almost never have to change the oil!:crazy:

I would change your oil when the OLM states to and call it a day. Oil changes are relatively cheap - engines are not.

sctb
03-23-2009, 01:15 PM
According to the service manual for the 5.3, "Excessive oil consumption, not due to leaks, is the use of 1 qt or more of engine oil within 2,000 miles."

Preliminary causes listed are:
-External oil leaks
-Incorrect oil level or improper reading of the stick
-Improper oil viscosity
-Continuous high speed driving and/or severe usage
-Crankcase ventilation system restrictions or malfunctioning components
-Worn valve guides / stems
-Piston rings broken, worn, or not seated properly
-Piston and rings improperly installed or not fitted to the cylinder bore.

For the 4.2, it's 1 qt within 1,500 miles. Same causes.

etperez22
03-23-2009, 01:43 PM
since I have yet to change it since I got it from the dealer since driving it approx 3k miles. The DIC states I have 70+% I don't think that is right. If that is the case I can drive 9k before It reaches 10% oil life left. I am hoping that it was just reset on accident prior to me getting the car.

Super 88
03-23-2009, 02:17 PM
since I have yet to change it since I got it from the dealer since driving it approx 3k miles. The DIC states I have 70+% I don't think that is right. If that is the case I can drive 9k before It reaches 10% oil life left. I am hoping that it was just reset on accident prior to me getting the car.

Probably not. The OLM is very accurate and takes into account many things, not just mileage. Some of the I6 engines will go about 12K miles before the OLM states to change it.

Too many people are hung up on 3K mile oil changes. The is from the 60's. A lot has changed since then.

markarock
03-23-2009, 11:40 PM
I would rethink your thoughts! :D

Going on your theory, you would almost never have to change the oil!:crazy:

I would change your oil when the OLM states to and call it a day. Oil changes are relatively cheap - engines are not.

Well, I rethought them, and calculated them. It was an interesting exercise, and confirmed my intuition. But, and it is a big but, there are assumptions that may or may not be correct. With that caveat, here goes:

Assume my 5.3 takes 5 quarts of oil.
Assume that my oil life is 6000 miles, for ease of calculation purposes.
Assume my motor uses one quart of oil every two thousand miles.
Assume that I add one quart of fresh oil every two thousand miles.
Assume that the oil that is "lost" or "burned" takes with it the "impurities" that are evenly disbursed throughout the oil.
Finally, assume the start mileage is 50,000

Now for the fun.

Mileage 52,000. Down one quart. Oil life of the remaining four quarts has decreased by one third. So, the 4 quarts of oil have 66.66% of the oil life left.
Add one quart.
What is the oil life of the new mix, which is 4/5 66.66% oil life oil and 1/5 of 100% oil life oil?
Easy. (66.66 x 4) + 100 divided by 5. The new mix has 73.3% oil life remaining.

Mileage 54,000. Down one quart. Oil life of the remaining 4 quarts has decreased by one third. It started at 73.3% and decreased by one third, so it is now at 48.9%
Add one quart.
What is the oil life of the new mix which is 4/5 48.9% oil and 1/5 of 100% oil?
Easy. (48.9 x 4) + 100 = 294.5 divided by 5 = 58.9% oil life remaining.

Mileage 56,000. Down one quart. Oil life of the remaining 4 quarts has again decreased by one third, so it is now at 58.9/3 x 2 or 39.3%.
Add one quart.
What is the oil life of the new mix which is 4/5 39.3% oil and 1/5 100% oil?
Easy. (39.3 x 4) + 100 = 257.2 divided by 5 = 51.4% oil life remaining.

Mileage 58,000. Down one quart. Oil life of the remaining 4 quarts has again decreased by one third, so it is now at 51.4%/3 x 2 = 34.3%.
Add one quart.
What is the oil life of the new mix which is 4/5 34.3% oil and 1/5 100% oil?
Easy. (34.3 x 4) + 100 = 237.2 divided by 5 = 47.4% oil life remaining.

Sure seems to me I could go a very long way before I needed to change my oil. In fact, you are right. I might never have to change my oil!

:excited::excited::excited:

dwright406
03-24-2009, 12:12 AM
Sure seems to me I could go a very long way before I needed to change my oil. In fact, you are right. I might never have to change my oil!

:excited::excited::excited:

I know you're joking (I hope, at least), but if at all serious, don't let the filter stay on for that long. A restricted oil filter is not good for an engine.


On the matter of the topic here, there is a service bulletin that was put into effect on 3/13/09


#PIP4492C: Excessive Oil Consumption and/or Blue Exhaust Smoke - Inspect PCV Baffle Drain Holes and Valve Train Oil Flow - keywords cover high lifter replacement rocker - (Mar 13, 2009)

Subject: Excessive Oil Consumption and/or Blue Exhaust Smoke - Inspect PCV Baffle Drain Holes and Valve Train Oil Flow


Models: 2009 Buick Lacrosse Super, Allure Super (Canada Only)

2004-2007 Buick Rainier

2004-2009 Cadillac CTS-V

2003-2009 Cadillac Escalade

2003-2006 Chevrolet SSR

2003-2009 Chevrolet Avalanche, Corvette, Express, Silverado, Suburban, Tahoe, Trail Blazer

2006-2009 Chevrolet Impala

2006-2007 Chevrolet Monte Carlo

2003-2009 GMC Envoy, Savana, Sierra, Yukon

2003-2009 Hummer H2

2008-2009 Hummer H3

2006-2008 Pontiac Grand Prix

2008-2009 Pontiac G8

2005-2009 Saab 97x

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI (Preliminary Information).

Condition/Concern:
On rare occasions, some customers may complaint of excessive oil consumption and/or blue exhaust smoke.

This may be the result of over-aggressive valve lifters and/or plugged PCV baffle drain holes in the valve cover that has the PCV vacuum pipe attached to it. This may also be the result of the same PCV baffle being improperly sealed to the valve cover if this concern has occurred since the vehicle was new or shortly after this valve cover was replaced.

Recommendation/Instructions:
Important: For 2007 Full Size Trucks and Utilities with the 5.3L Engine (RPO LC9 - VIN 3), please refer to the latest version of PIP4574 for recommendations. For all others, refer to the recommendations below.

If bulletin 01-06-01-011 identifies excessive oil consumption but SI diagnosis does not isolate the cause of it, remove the valve cover that has the PCV vacuum pipe attached to it and perform the following suggestions:

1) Check for an over-aggressive lifter by monitoring oil flow at the top of each push rod with the engine at idle. It should not be necessary to raise the RPM to check for an over-aggressive lifter. Very little flow should be observed at an idle. It will be obvious if an over-aggressive lifter is present because its flow will be greatly excessive when compared with the others and a great deal of cleanup will be required. Replace any over-aggressive lifter(s) and re-evaluate the concern.

2) Inspect the PCV baffle drain holes shown below to see if they are plugged with hardened oil deposits. If they are plugged, replace the valve cover, ensure that the customer is changing their oil according to the maintenance schedule in their owner's manual, and re-evaluate the concern. Generally, this would not be a concern until several thousand miles have accumulated.

3) Inspect the PCV baffle to ensure that it is properly sealed to the valve cover by flipping it over and adding a little oil to the corner of the valve cover as shown below. The oil should stay in place as shown on the 2 outer valve covers below. If the oil drains into the PCV baffle as pointed out on the middle valve cover below, replace the valve cover. Generally, if this is the cause of the concern, it would have been present early in the life of the vehicle or shortly after valve cover replacement.

Important: If Step 2 or 3 leads to valve cover replacement, perform Step 3 on the replacement valve cover before installing it.

http://gsi.xw.gm.com/image_en_us/gif/000/002/195/2195879.gif
PCV Baffle Drain Holes Described in Step 2

http://gsi.xw.gm.com/image_en_us/gif/000/002/245/2245145.gif
PCV Baffle Comparison Described in Step 3

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.



And while I'm at it, here's the Oil Consumption Diagnosis from the GM Service Information.

Excessive oil consumption, not due to leaks, is the use of 1 L (1 qt) or more of engine oil within 3,200 kilometers (2,000 miles).

The causes of excessive oil consumption may include the following conditions:

External oil leaks


Incorrect oil level or improper reading of the oil level indicator

With the vehicle on a level surface, run the engine for a few minutes, allow adequate drain down time, 2-3 minutes, and check for the correct engine oil level.

Improper oil viscosity

Refer to the vehicle owners manual and use the recommended SAE grade and viscosity for the prevailing temperatures.

Continuous high speed driving and/or severe usage

Crankcase ventilation system restrictions or malfunctioning components

Worn valve guides and/or valve stems

Worn or improperly installed valve stem oil seals

Piston rings broken, worn, or not seated properly

Allow adequate time for the rings to seat.

Replace worn piston rings as necessary.

Piston and rings improperly installed or not fitted to the cylinder bore



Hope this helps :undecided

etperez22
03-24-2009, 11:35 AM
That is great news.. If there is a service bulletin is that almost like a recall? will the manufacturer pay for the repairs or diagnosis and etc?

Super 88
03-24-2009, 11:42 AM
Well, I rethought them, and calculated them. It was an interesting exercise, and confirmed my intuition. But, and it is a big but, there are assumptions that may or may not be correct. With that caveat, here goes:

Assume my 5.3 takes 5 quarts of oil.
Assume that my oil life is 6000 miles, for ease of calculation purposes.
Assume my motor uses one quart of oil every two thousand miles.
Assume that I add one quart of fresh oil every two thousand miles.
Assume that the oil that is "lost" or "burned" takes with it the "impurities" that are evenly disbursed throughout the oil.
Finally, assume the start mileage is 50,000

Now for the fun.



That is where or at least one of the places your so called logic is flawed. Just because you are losing oil does NOT mean all the impurities are going with it.

Plus what another poster said - your oil filter needs to be changed occasionally as well.

But - hey it's your engine. We'll be looking for your next thread a little later on saying:
"Engine blown - where to get a new one". :D

Robert1101
03-24-2009, 11:47 AM
Sure seems to me I could go a very long way before I needed to change my oil. In fact, you are right. I might never have to change my oil!

:excited::excited::excited:

I think you are forgetting about the sulfuric acid that is forming in the oil that is still in the engine. Not to mention the fuel blow by that is also concentrating in the existing oil. You could end up desolving the engine from the inside. The existing oil will form sluge and start plugging up oil passages. Is it really worth it?????:crazy:

Super 88
03-24-2009, 12:01 PM
I think you are forgetting about the sulfuric acid that is forming in the oil that is still in the engine. Not to mention the fuel blow by that is also concentrating in the existing oil. You could end up desolving the engine from the inside. The existing oil will form sluge and start plugging up oil passages. Is it really worth it?????:crazy:

Exactly. I've had engines apart that were oil burners before they died and there would typically be a LOT of sludge. I mean LOTS of it! (Get the idea). :)

dwright406
03-24-2009, 12:12 PM
That is great news.. If there is a service bulletin is that almost like a recall? will the manufacturer pay for the repairs or diagnosis and etc?


Well I'm fairly new at this job (I've been working at a GM dealership for a month now), so I'm not 100% certain, but that information is directly from the GM Service website that we (GM Techs) have to work by.

That particular PI (Preliminary Information) was just recently posted, and the fact that it's considered Preliminary Information leads me to believe that there have been enough cases of the same problem to warrant a bullitin and possibly could become a recognized campaign (A known defect that GM will pay to correct, similar to a recall).

Again I'm new at working for GM, so this is my best guess.
Today is my day off, so tomorrow I'll ask someone who knows better how PI's and service bullitins work.

markarock
03-24-2009, 12:25 PM
I know you're joking (I hope, at least)...

Me, Joking? Surely you jest. :crazy::nono::tiphat

Actually, the numbers seem to support my position, as the below calculations, done a different way seem to show. I agree that changing the filter is recommended, even though the oil might still be good, and that has the added benefit of adding additional fresh oil (I do fill my filter with fresh oil before installation). But, if I am going to go to the trouble to change my filter, I'm going to change my oil. Never fear--this thread is just some interesting discussion.

Also, I should have mentioned in my initial assumptions that it is my understanding that oil itself doesn't wear out. The actual oil molecules retain their shape and properties in normal operations; it is just the additive package that becomes depleted. So, even though used oil has reached the end of its life, all that means is that the additive package has been exhausted, not that the oil itself isn't any good any more.

That cleared up, lets take another mathematical journey.

Start: 5 quarts at 100% useful life. Max life is 6000 miles.

2000 miles, down 1 quart.
So, the remaining 4 quarts have lost 1/3 of their useful life.
So, add 1 quart of 100% useful life oil.
New mix:
80% (4 quarts) has 66.66% oil life remaining
20% (1 quart) has 100% oil life remaining
Life of the blended mix =:
66.66 x 4 = 266.64
100.0 x1 = 100
Total = 366.64
Life remaining in blended mix = 366.64/5 = 73.3%

At 4000 miles, down another quart.
So, the remaining 4 quarts have lost 1/3 of their useful life. This time, let's follow each of the quarts individually.
Before, we had 4 quarts of our original/starting oil that had 2/3 of its life remaining. In these 2000 miles we have lost an additional 20% of this original oil. We added one quart, and we have lost 20% of that make-up oil as well. Then, we add one more quart of new oil to bring us back up to the full mark.
Our new mix now looks like this:
64% (3.2 quarts) now has 1/3 of its life left
16% (.8 quart) now has 2/3 of its life left
20% (1 quart) now has 100% of its life left

At 6000 miles, down yet another quart (this is the third quart we need to add).
So, the remaining 4 quarts have lost and additional 1/3 of their useful life. Again, let's follow each of the quarts individually.
Before, we had 3.2 quarts of our original/starting oil with 1/3 of its life remaining, .8 quart of our first quart of make-up oil with 2/3 of its life remaining, and 1 quart of additional make-up oil with 100% of its useful life remaining. In these miles between 4000 and 6000 we have lost an additional 20% of this mix of original and two quarts of make-up oil. Now we add one more quart of new oil to bring us back up to the full mark.
Our new mix now looks like this:
51.2% (3.2 quarts) now has zero% of its life left (the additive package is shot)
12.8% (.64 quart) now has 1/3 of its life left
16.0% (.8 quart) now has 2/3 of its life left
20% (1 quart) now has 100 % of its life left

Just looking at the numbers, you can see that:
51.2% = dead additive package
20% is at 100% additive package
16% is at 66.66% additive package
12.8% is at 33.3% additive package

Guesstimating, you can see that the mix of oil still has an additive package that is just below halfway exhausted, which is what the first post concluded.

QED

:woohoo:

markarock
03-24-2009, 12:41 PM
I think you are forgetting about the sulfuric acid that is forming in the oil that is still in the engine. Not to mention the fuel blow by that is also concentrating in the existing oil. You could end up desolving the engine from the inside. The existing oil will form sluge and start plugging up oil passages. Is it really worth it?????:crazy:


No, it is not really worth it. I plan to change my oil, but not when the DIC says, but rather 4000 miles beyond that, approximately.

Now, my discussion was just to make a case for what I plan to do. YMMV.

But think about this. Back in the day, the recommendation was to change oil every 3000 miles. Today there are still those who say to others what you are saying to me, "Is it really worth it?????" Well, it is very hard to argue with that logic. Very hard. But tests and research and advances in oil additive packages chemistry and tighter manufacturing tolerances all combine to make longer oil change intervals risk free. By the same logic, adding a sufficient quantity of make-up oil should do the same thing.

No, I'm not forgetting about sulfuric acid in the oil. That is what the additive package neutralizes. It is not present in the oil unless the additive package has used up all of its ability to neutralize the acid.

Nor am I forgetting about the fuel dilution in the oil. I just know that running the engine at operating temperature will boil off any fuel in the oil, and any moisture as well. I also know that my truck gets reasonable doses of Interstate driving on my wife's work commute each day, so the miles being put on the oil are relatively "easy" miles.

Again, I understand the risks, and I don't plan on not changing my oil. But I do plan on extending my oil change interval by about 40% because of all of the make-up oil I am adding. Is it a risk? I don't think so given the numbers. But, just like others who continue to adhere to 3000 mile oil change intervals despite the overwhelming evidence that it is anachronistic, your opinion may differ. All I'm offering is some food for thought and discussion. And perhaps playing a bit of Devil's Advocate just to stir folks up. :)

:tiphat

Robert1101
03-24-2009, 01:04 PM
No, I'm not forgetting about sulfuric acid in the oil. That is what the additive package neutralizes. It is not present in the oil unless the additive package has used up all of its ability to neutralize the acid.

Nor am I forgetting about the fuel dilution in the oil. I just know that running the engine at operating temperature will boil off any fuel in the oil, and any moisture as well. I also know that my truck gets reasonable doses of Interstate driving on my wife's work commute each day, so the miles being put on the oil are relatively "easy" miles.

:tiphat
When you neutralize H2SO4 you will usually form a salt of one form or another. Not good for the motor. It does not go away.
Oil and gas form other compounds that will not boil off the fuel when heated. Point is: years ago when carbs ran fuel around rings and engines ran very hot, you could still smell the gas on the dipstick. It did not boil off. True, water will boil off but fuel will not. This is your truck and your engine. I would like to hear how it is running in, lets say 75K miles down the road.
My :m2:

91RS
03-24-2009, 09:13 PM
That is great news.. If there is a service bulletin is that almost like a recall? will the manufacturer pay for the repairs or diagnosis and etc?

No, bulletins are just information about "common" concerns and are meant for GM service techs to aid in diagnosis. A recall or a special policy is when GM will cover the repair.

markarock
03-26-2009, 08:06 AM
Here is a helpful link that supports my thinking. Especially the quote about oil not wearing out.

http://www.blackstone-labs.com/newsletter.html?utm_source=Blackstone's+March+'09+ Engine+Newsletter&utm_campaign=893cb1d9d8-March_Gas_Diesel_Newsletter03_31_2008&utm_medium=email

In terms of the "salts" point, aren't they solids, and wouldn't they be captured by the filter?

As for the fuel in the oil not boiling off point, two comments. First, today's engines burn so efficiently that there is rarely if ever fuel in the oil. Second, gasoline does evaporate quickly, so even if it doesn't boil off, it will evaporate away and be burned by the engine through the PCV system. Yes, there may be some additives that remain, but nobody has shown (me) that they have a deleterious effect upon motor oil in a crankcase.

Finally, as for the assumption that oil "lost" or "burned" doesn't take its share of impurities with it, I beg to differ. Let's take leaking oil, as that is the easiest case. Leaking is the same as draining in my book. If I drained a quart of hot oil, or sucked a quart out the dipstick tube, it would contain its share of the impurities in suspension. So on a full engine (6 quarts I now see from the Owner's Handbook, not the 5 quarts I assumed--you can tell I haven't had to change oil yet), draining one quart will take 1/6 of the contaminents etc. with it. I submit the same is true if the oil goes down the valve guides or through the PCV system.

Just my thinking. YMMV.

Super 88
03-26-2009, 11:52 AM
Finally, as for the assumption that oil "lost" or "burned" doesn't take its share of impurities with it, I beg to differ. Let's take leaking oil, as that is the easiest case. Leaking is the same as draining in my book. If I drained a quart of hot oil, or sucked a quart out the dipstick tube, it would contain its share of the impurities in suspension. So on a full engine (6 quarts I now see from the Owner's Handbook, not the 5 quarts I assumed--you can tell I haven't had to change oil yet), draining one quart will take 1/6 of the contaminents etc. with it. I submit the same is true if the oil goes down the valve guides or through the PCV system.

Just my thinking. YMMV.

Problem is - if your "thinking" is right, and the lost oil DOES take some impurities with it, what about the other 5 - 6 quarts in the engine (depending on the engine).

Personally I think this is really a moot point. I think you just like to "discuss". As I said before, if you want to do it to your truck be my guest.
But I certainly would NOT recommend it.

Plus like I said before - you can theorize all you want - but I've seen a LOT of engines tore down. Most of these were oil burners were people were adding oil constantly - some as much as every 200 - 300 miles. They had the same theory as you - since I'm adding so much oil I don't need to change it.
Let's just say it was not a pretty site.

markarock
03-26-2009, 05:49 PM
I think you just like to "discuss".

BINGO! Guilty as charged. So, no need to read further. Unless you too just like to discuss.`:bonk:

Problem is - if your "thinking" is right, and the lost oil DOES take some impurities with it, what about the other 5 - 6 quarts in the engine (depending on the engine).

Hmmm. I'm dissed because I "just like to 'discuss'", yet you ask me a question. Hmmm. Well, I've been invited to respond, it seems, :) so: The remaining oil in the engine has much the same percentage of contaminents as the oil that was lost (but not exactly, if we are being precise). If one quart was lost, then 5 quarts remain. Add one quart, and you have 5 contaminated quarts and one uncontaminated quart, so overall the percentage of contaminents in the engine oil is lower after the new quart is added than it was before the one quart was added.

Plus like I said before - you can theorize all you want - but I've seen a LOT of engines tore down. Most of these were oil burners were people were adding oil constantly - some as much as every 200 - 300 miles. They had the same theory as you - since I'm adding so much oil I don't need to change it. Let's just say it was not a pretty site.

I have torn down my share of engines as well. And built new ones. Typically the oil burners got to be that way because the rings became stuck, or the valve guides wore excessively, usually because the engine was abused BEFORE a new quart of oil started to get thrown in every few hundred miles. If the engine had been cared for in the first place, it never would have gotten to the point of being an oil burner. Of course, some were oil burners simply because of sloppy manufacturing tolerances and ring and valve guide wear that had nothing to do with the frequency of oil and filter changes.

Super 88
03-26-2009, 05:53 PM
Hmmm. I'm dissed because I "just like to 'discuss'", yet you ask me a question. Hmmm. Well, I've been invited to respond, it seems, :) so:

Not really. Haven't you ever heard of a rhetorical question?

(End of feeding the troll) :D

markarock
03-26-2009, 10:26 PM
Not really. Haven't you ever heard of a rhetorical question?

Hmmmm. Is THAT a rhetorical question? Hmmm? :crazy::crazy:

Super 88
03-27-2009, 12:48 AM
Hmmmm. Is THAT a rhetorical question? Hmmm? :crazy::crazy:

It might be - it might not be! :laugh:

Like I said - no more feeding the troll.

Denali n DOO
04-11-2009, 10:46 AM
I didn't see this thread. My 5.3 Denali puffed blue smoke yesterday, first time seen. Oil level is below cross hatched area on dipstick. Have 17% left on DIC but doing oil change anyway. My tail pipe also is very blackened. To the dealer on Monday with that PIP info bulliton to check PVC drain areas. Well at least I'm not the only one with the problem. If there is a fix out there for exssevive oil consumption I hope my warranty covers it. Any other 5.3 owners with this issue?

boosteddakota
04-12-2009, 07:31 PM
i have never had this problem with my tb but my mom bought her 03-04 envoy forgot what year it was, but since day 1 she has had this problem. she bought it off the showroom floor. 2 miles on it. she changes the oil every 3000 miles on the dot. she is the only driver and she does the same exact driving route and sometimes the oil level is right up where it should be and others its 1-2 quarts low. i dont get it. im glad mine isnt like that

Denali n DOO
04-13-2009, 07:57 PM
I know you're joking (I hope, at least), but if at all serious, don't let the filter stay on for that long. A restricted oil filter is not good for an engine.


On the matter of the topic here, there is a service bulletin that was put into effect on 3/13/09




And while I'm at it, here's the Oil Consumption Diagnosis from the GM Service Information.



Hope this helps :undecided

I took the Envoy to the dealer today to inquire as to the blue smoke. He said valve covers are ordered under warranty as per #PIP4492D. What is the difference between #PIP4492C (as decribed above) and #PIP4492D??? Any ideas.

91RS
04-13-2009, 08:08 PM
D is just another revision to C.

Denali n DOO
04-13-2009, 09:43 PM
Thanks...

lynch55
04-13-2009, 10:20 PM
I have been following this thread and I have come to the conclusion that indeed I am confused and I will change my oil religously and will not assume that it will not last longer just by adding a quart every 2000miles!:confused:

LEGDAIN
05-02-2009, 08:55 AM
HELLO i have a 2006 trailblazer 5.3l engine.it consumes about 1 1/2 to 2 quarts of oil every 3,000 miles.it has 47,000 miles on it and is still under gm extended warranty.gm is doing an oil consupmtion test on it now.which means they change the oil and you bring it back to them when it needs more oil and they will keep up with the amount of oil it consumes.the kicker here is that they all say there is an acceptable level of consumption, however none of them knows what it is.i have have taken it to three dealerships and talked to two others.in my mind this is absolutely unacceptable.my 1988 c1500 with 250,000 miles didnt use oil like this.i also noticed that when the dealer ship changed my oil and started the "test" they accidentally overfilled it by a quart or so. By the time i caught it and got it back to them it was barely showing overfull and they denied it was ever overfull.the thing that really gets me here is that if they say this is acceptable then what good is the cute little oil life moniter.i will run completely out of oil before it tells me to change it.thanks for any ideas or for just letting me vent about it.

Super 88
05-02-2009, 11:52 AM
Hthe thing that really gets me here is that if they say this is acceptable then what good is the cute little oil life moniter.i will run completely out of oil before it tells me to change it.thanks for any ideas or for just letting me vent about it.


I see what you are saying. At the rate you are going you could put almost all new oil in there before the light tells you to change it.
Since the Oil Life Monitor works off a computer algorithm, it measures engine rpms, temps, load, stuff like that. But it doesn't know what kind of oil you have in there, how much new oil is in the mix, or even IF there is any oil in there.

I agree this amount of oil usage seems excessive. But this has always been a problem with car makers. I've heard some of them say 1 quart in 1,000 miles is "normal".
My I6 doesn't use any oil in between changes, which is about 7 - 8,000 miles.

Denali n DOO
05-02-2009, 11:59 AM
HELLO i have a 2006 trailblazer 5.3l engine.it consumes about 1 1/2 to 2 quarts of oil every 3,000 miles.it has 47,000 miles on it and is still under gm extended warranty.gm is doing an oil consupmtion test on it now.which means they change the oil and you bring it back to them when it needs more oil and they will keep up with the amount of oil it consumes.the kicker here is that they all say there is an acceptable level of consumption, however none of them knows what it is.i have have taken it to three dealerships and talked to two others.in my mind this is absolutely unacceptable.my 1988 c1500 with 250,000 miles didnt use oil like this.i also noticed that when the dealer ship changed my oil and started the "test" they accidentally overfilled it by a quart or so. By the time i caught it and got it back to them it was barely showing overfull and they denied it was ever overfull.the thing that really gets me here is that if they say this is acceptable then what good is the cute little oil life moniter.i will run completely out of oil before it tells me to change it.thanks for any ideas or for just letting me vent about it.

I had vavle covers replaced under warranty (39500miles). It seems to run quieter at start up. I'm waiting to accumulate a few miles and check oil level. I was burning it cause blue smoke and tail pipe black. I wish I would have done an emissions test before and after, likely been able to determine if its running cleaner after the covers were installed. Not sure how plugged drain Baffles in the vale cover causes it to burn oil. Chime in if anyone knows that answer.

gmcierra
06-08-2009, 07:45 PM
any results?

rrufast
09-13-2009, 03:57 PM
Any ideas on why this Service bulletin covers 2003+ TB's but NOT the 2002?

91RS
09-13-2009, 04:06 PM
Any ideas on why this Service bulletin covers 2003+ TB's but NOT the 2002?

Because its only for V8s and you couldn't get a V8 in 02.

rrufast
09-14-2009, 01:48 AM
Duhhhh.. I didn't read that far into it... My bad.

Attached are a few pics of where I have now determined mine is leaking.. These were taken when changing oil yesterday... You can see the frame rail in a couple of them..

I'm no mechanic, so I'm not sure what part this is coming from. It looks like where the half shaft mates to the transmission just above the oil pan? Correct me if I'm wrong.

http://i257.photobucket.com/albums/hh212/rrufast/Trailblazer%20stuff/DSC04867.jpg

http://i257.photobucket.com/albums/hh212/rrufast/Trailblazer%20stuff/DSC04868.jpg

http://i257.photobucket.com/albums/hh212/rrufast/Trailblazer%20stuff/DSC04869.jpg

http://i257.photobucket.com/albums/hh212/rrufast/Trailblazer%20stuff/DSC04870.jpg

91RS
09-14-2009, 08:03 AM
That's not engine oil, that's gear oil. That is your front differential. From your pictures, the left front axle seal is definately leaking but the pinion seal may be leaking as well. I would try and get that fixed soon, looks like it's been leaking for a while and you don't want that front diff to run out of fluid.

markarock
09-14-2009, 08:52 AM
Check out this thread.

http://forums.trailvoy.com/showthread.php?t=45202

rrufast
10-08-2009, 09:52 PM
I haven't had time to check the differential yet.. but on another look today, it seems like the drain bolt may have possibly come loose a slight little bit and allowed seepage which is evidenced by the grime buildup.

These are photos of the differential and the drain bolt, correct? I'll search around and see if I can find a thread on draining/replacing the fluid...

http://i257.photobucket.com/albums/hh212/rrufast/Trailblazer%20stuff/DSC04973.jpg

http://i257.photobucket.com/albums/hh212/rrufast/Trailblazer%20stuff/DSC04970.jpg

http://i257.photobucket.com/albums/hh212/rrufast/Trailblazer%20stuff/DSC04979.jpg

91RS
10-08-2009, 10:22 PM
The axle seal is leaking, not the drain plug.

rrufast
10-08-2009, 10:40 PM
After reading the post above mine (with the link) I figured out it was the axle seal.. This looks like something I'll wait to do at the college's shop. My dad is an instructor at a Comm College back home, so I have full access to the shop and, more importantly, his knowledge, so long as I drive the 2 hours to get there... Looks like a trip is definitely in order... soon.

No noise from the half shaft yet, so I'm assuming that the CV joint is still fine. I'll order the seal that was provided in the previous link from my local dealership. What type of gear oil is to be used as a replacement when draining refilling the differential?

91RS
10-08-2009, 11:11 PM
75W-90 full synthetic. You need to use a high quality synthetic. I would also suggest changing out the fluid in the rear diff. as well.

markarock
10-08-2009, 11:23 PM
The front takes ordinary 75W-90 synthetic gear oil. Pretty much any major brand will be fine, in my opinion.

rrufast
10-09-2009, 05:30 PM
I did a quick drain/fill a few minutes ago... Used 75W-90 Synthetic Blend SuperTech brand. As soon as they return from NJ (next week) I plan on draining/filling again with a higher quality fully synthetic diff oil. I need to make plans to replace the leaking diff seal soon as well.

Will read and re read the above procedure/link to make sure I can tackle this in the driveway...

The gear oil drained out was dirty black and had teh normal burnt gear oil smell.. didn't have a clean drain pan to check for metal bits butu will do that on their return when I drain/fill again. On a good note, the existing oil level wasn't too low. I could feel it when I stuck my pinky in the fill hole and bending it down just a hair....

I love this forum. Not only do I learn.. I save money and get the satisfaction of being able to do things myself...:thumbsup::thx

mattfuria
11-02-2009, 02:40 PM
Same "missing oil" problem with my 06 Envoy Denali. Had it for about 6 months now. Usually by the time it reaches 30% oil life, about 3 quarts have disappeared. Anyone who's had this PIP done, is the problem solved afterwards?

jwh463
11-12-2009, 12:03 PM
my 05 5.3 has been doing the samething for about a yr. It currently has 73k miles. I have always ran Mobil One 5/30 and let the oil change guy talk me into Castrol GTX High Mileage and I have noticed no change. Still a 2-3 qts every oil change (7.5k miles). Next oil change I am going to try 10/30 Castrol Edge.

I have noticed the oil use is not noticeable UNTIL I take a road trip over 100miles or so at high speed (75-85mph). I have been monitoring oil use very closely (2-3 times per week). After I get home from a road trip I need almost a whole quart to fil it back up. My best amateur guess is that the 5.3 doesn't like the high speed runs.

weird thing is my 03 Silverado with 5.3 has about 80k miles and goes a whole oil change without using any oil. :undecided

quag421
11-17-2009, 07:35 PM
Hope someone can help, searched the threads but didn't see my issue. Bought a used (Certified) 06 Denali. To be honest we have had it in three times in 3 months, mostly little crap.

I haven't changed the oil yet, but checked it before a trip over Christmas and needed to add a quart. Just thought the dealer never topped off so didn't think much about it. Checked at the end of the trip, needed another 1/2 quart. And just added another 1/2 quart today.

Call me crazy but I shouldn't have to be adding 2 quarts between oil changes with 34K on it. No leaks that I can find underneith and nothing on the garage floor. Not seeing any smoke or signs of burning oil. Engine is running fine, and not throwing any codes.

We had a 04 Envoy with the I6 and over 90K when I traded it in. Never once did I add oil btwn oil changes. Getting a little concerned we my have a problem child.

Any ideas?:confused:

Very sorry for the lack of follow up, but I probably should close this out. As may have said the dealer indicated that 1 qt per 2000 miles is normal (though I have never had a car do this) I keep a close watch and it has not gotten worse. Nor do I ever see any smoke, and the car runs smooth. I have found that when I run 10W30 (as I always have in the summer months) it seems to be less of an issue. I like the motor and the car. Great for towing our boat, and mileage is better then the I6, however find it hard to believe that a quart per 2K is acceptable. Can't imagine someone with no knowledge at all of car mechanics or those that never check their oil, would not have huge issues.

markarock
11-18-2009, 08:27 AM
[I] find it hard to believe that a quart per 2K is acceptable.

Actually, I remember back when a quart per 1000 miles was the norm, and if you went 1500 miles on a quart, you had a great motor. I also remember the common wisdom being that you "needed" to use some oil because that was a signal that the top rings were being lubricated, and if you had an amazing engine that would get 2000 miles/quart, it would be dead prematurely because the top rings wouldn't be getting any lubrication.

So much for common wisdom.

Mine uses a quart every 2000-2500 miles depending on the type of driving being done, and I'm ok with it. Broke enough to find, but not broke enough to fix.

quag421
11-18-2009, 10:33 AM
Actually, I remember back when a quart per 1000 miles was the norm, and if you went 1500 miles on a quart, you had a great motor. I also remember the common wisdom being that you "needed" to use some oil because that was a signal that the top rings were being lubricated, and if you had an amazing engine that would get 2000 miles/quart, it would be dead prematurely because the top rings wouldn't be getting any lubrication.

So much for common wisdom.

Mine uses a quart every 200-2500 miles depending on the type of driving being done, and I'm ok with it. Broke enough to find, but not broke enough to fix.

Yeh I agree that back in the 70's it was acceptable, and in my old cars I never went anywhere with out a couple quarts of oil in the trunk, but not anymore. Shoot my impala is pushing 100K and gets driven hard (company car) doesn't use a drop in 6000 miles, nor did the I6 I had. Again GM says this is normal and seems to run fin otherwise, so I will just have to watch.

CSDenali
11-23-2009, 06:10 PM
Mine continues to "consume" the oil. I have been running Valvoline 5W30. On average, I go through 2 quarts between oil changes. (every 3k miles) Seems excessive to me, as I had a Tahoe and Avalanche that always stayed on the full mark. :mad:

jwh463
11-25-2009, 04:35 PM
thought I would update you on trying new oil/wt (10/30)

well I changed the oil to 10/30 Castrol Edge. I just left DFW and drove to Marquette MI; over 1300 miles. I did it in one trip (19.5hrs) at speeds with cruise set from 65-80 and runs up to 95mph a few times. I got here last night and checked the oil. My pristine clear oil is now very dirty and it needs a whole quart of oil. I don't know what else to do...I guess just accept it:confused:

LEGDAIN
11-25-2009, 05:43 PM
Hello all.well i'm still consuming oil at an alarming rate,atleast in my eyes anyway.i did a really good test on it my last oil change .it comes to this.my 5.3l is using 46oz of oil in 2,261 miles.that comes to .o2oz per mile if my math is correct.so in 3,000 miles,eventough the built in algorithum tells me to change it about 5 to 6,000 miles,it consumes 60oz of oil (1.875qt).i have just talked to gm customer service who says 1qt every 2,000 miles is acceptable.so 1 1/2 qt in 3,000 miles.would anyone like to take a bet. When the dealership does this test it will pass.

91RS
11-25-2009, 07:01 PM
Has no one had the bulletin for the PCV that was posted earlier in this thread done?

LEGDAIN
11-25-2009, 11:06 PM
I have not had any pcv work done.But I have had this vehicle at three seperate dealerships and have filed a formal complaint with GM and no one has said anything to me about it.I got this vehicle with 30,000 miles on it, so maybe it was already performed.Not sure really.I am sure at 30,000 miles they already knew ithad this issue, so its very ossible its already been done.

jwh463
11-25-2009, 11:46 PM
Has no one had the bulletin for the PCV that was posted earlier in this thread done?

thought the 5.3 doesnt have a PCV?

lynch55
11-26-2009, 12:35 AM
4.2 has no pcv. v-8 does!

91RS
11-26-2009, 10:04 AM
4.2 has no pcv. v-8 does!

They both have PCV systems.

jwh463
11-26-2009, 05:22 PM
anybody got a photo of location on 5.3L ? Maybe I could replace it before I leave Saturday

WOOLUF1952
11-26-2009, 11:08 PM
They both have PCV systems.

:iagree: But there is no replaceable PCV valve on the I6. .The PCV valve is in the rear drivers side valve cover on the 5.3.

RedEnvoyDenali
11-26-2009, 11:28 PM
I too have a 06 Denali with over 40K miles. I will use 1/2 quart between changes done on the Oil Monitor about 8-10K. I would consider this level of oil usage unacceptable but what do you do if the dealerships just say it is normal. Please keep us informed if you get any kind of positive response from anyone regarding this situation.

By the way HAPPY THANKSGIVING to all our American cousins.:tiphat:grouphug:

markarock
11-27-2009, 11:07 AM
I will use 1/2 quart between changes done on the Oil Monitor about 8-10K. I would consider this level of oil usage unacceptable...

Well, a half quart in 8,000 miles is fantastic in my experience. I'll use about 2.5 quarts in that many miles. You should count your blessings! IMHO.

jwh463
11-27-2009, 11:44 AM
:iagree: But there is no replaceable PCV valve on the I6. .The PCV valve is in the rear drivers side valve cover on the 5.3.

I went to a GMC dealer this morning; 05 5.3l does NOT have a PCV, 2004 was the last year for a PCV on the 5.3L

91RS
11-27-2009, 07:53 PM
Maybe the last year for a valve, but it still has a PCV system. ALL GM vehicles have a PCV system. It may not have a replaceable valve but it still has a PCV! The bulletin posted on page two covers 03-09 Trailblazers with the 5.3L.

RedEnvoyDenali
11-28-2009, 12:30 AM
Quote:
Originally Posted by RedEnvoyDenali View Post
I will use 1/2 quart between changes done on the Oil Monitor about 8-10K. I would consider this level of oil usage unacceptable...
Well, a half quart in 8,000 miles is fantastic in my experience. I'll use about 2.5 quarts in that many miles. You should count your blessings! IMHO.

Sorry wasn't very clear. I find my oil mileage very acceptable but if I got a quart to 2K miles I wouldn't be very happy.

Was thinking about this problem today, would a compression check give any clue to as where the oil is going?:confused::confused:

markarock
11-28-2009, 10:29 AM
...would a compression check give any clue to as where the oil is going?:confused::confused:

Possibly, but probably not. If you suspect that your rings are worn, then you can do a compression check and if you have low compression, you can toss in a couple tablespoons of oil into the cylinder and do another check. It the compression reading is higher the second time, then the extra oil has "sealed" the compression in, and the conclusion is that the rings are worn and should be replaced.

If the compression does not increase with the addition of the oil, then the valves are suspect. The are not seating/sealing properly.

Oil burning in the cylinder can only occur in one of three ways:

1. It leaks past the rings

2. It is sucked down the valve guides (intake, exhaust, or both)

3. It finds its way into the intake airstream somehow--either via a bad pcv valve, or via an oil leak into the intake track.

A compression check can only rule out possibility #1.

atv hauler
11-28-2009, 11:10 AM
Maybe the last year for a valve, but it still has a PCV system. ALL GM vehicles have a PCV system. It may not have a replaceable valve but it still has a PCV! The bulletin posted on page two covers 03-09 Trailblazers with the 5.3L.

:iagree:As far as I know all modern engines have (pcv) positive crankcase ventilation systems but as mentioned,with or without a REPLACEABLE valve.

emvoy
11-30-2009, 02:44 PM
Just Think of it as a everlasting oil change:crazy:... my 5.3 goes through about 1-1/12 quarts between oil changes (every3500-5000 miles)... I figure screw it!!! it runs good dealer wont do crap, and i got four years(extended warranty) to blow it up and get a new engine. i just hope it doesnt go after the warranty:bonk: probably not the best plan but like i said dealer wont do crap about it

02Bravado
12-02-2009, 12:45 AM
My 4.2L recently seemed to develop some oil consumption issues. Over the weekend, I happened to check all of the fluids and noticed that I was about 1 quart low and its only been about 3k miles (I usually go 7500 or so on synthetic). Previously, it seemed that I would get most of my oil back out during oil changes. So, I looked and found this thread, pretty good info. In my last oil change, I went with Mobil 1 synthetic 5w30 weight which might be the problem. I was thinking that the lower weight Mobil 1 would flow better and possibly help a little on the fuel econ. All previous changes were done using Shell Rotella T Synthetic 5w40. The Rotella is meant for trucks (passes GMs test specs) and so thought this might be better for longevity but also knew that I was sacrificing some performance due to the heavier weight oil. If that does not help, I'll look into cleaning the PCV areas on the engine. Just thought I would share since a few seemed to be checking different types of oil. It might be worth a try. Also another poster mentioned they had an 88 GMC truck that did not consume oil. I have a Home depot cruiser '88 GMC with a 5.7 with 127k on and does not use a drop of oil between changes.

jwh463
12-02-2009, 12:10 PM
well I got back from Michigan late Saturday. I checked the oil at every fuel stop; in St Louis I needed a half qt and did not want to open a new bottle of Edge so I bought and added STP..I figure WTF it is burning it anyway. I did notice a 5lb boost in oil pressue. When I got home I was one full qt low. I changed the oil and put in Castrol HIMILEage 10/30. I am done fighting this battle with high end expensive oil. I will take to the dealer and have the PCV thing checked but now I have bigger problems...water pump is out and being repaired today.

CSDenali
12-02-2009, 10:23 PM
Ha! I did my water pump last summer. Hmm . . . Excessive oil consumption and faulty water pumps. Could they be related? Probably not. However, I can't resist adding to the conspiracy theory regarding my engine. :duh:

Ntrsandmann
12-10-2009, 05:47 PM
Hi all,

You all are going to love this...

Bought my 2006 Saab 97x a year ago, it was my first GM vehicle.

It had 35k miles when i bought it, and actually was burning oil then...

At 48k miles took it to dealer and described problem, they suggested an oil consumption test done under warranty, but i had to pay for the oil change...

Took it back at 49800 miles and guess what? it was 2 quarts low!

My schedule does not allow frequent trips to the dealer so i wnt back to have this issue taken care of at 54k...

To be told by the new service manager that my car is out of warranty and that 1 Qt. every 900 miles is NORMAL!! I showed him the service advisory and the manual where it specifically states 1 Qt. every 2k miles...

Was referred to Saab and they said the dealer had denied my claim and that there was NOTHING I COULD DO!!

IT seems that there are so many with this issue, a class action lawsuit is in order. Please respond to me if there is any interest in this as I will be suing anyway. My first and Last GM vehicle. POS!! :hissy:

WOOLUF1952
12-10-2009, 08:15 PM
I would call GM customer service before a lawyer. Also, tell the dealer you heard GM is still looking for dealers to cut to save money.

Denali n DOO
03-06-2010, 07:05 PM
Just Think of it as a everlasting oil change:crazy:... my 5.3 goes through about 1-1/12 quarts between oil changes (every3500-5000 miles)... I figure screw it!!! it runs good dealer wont do crap, and i got four years(extended warranty) to blow it up and get a new engine. i just hope it doesnt go after the warranty:bonk: probably not the best plan but like i said dealer wont do crap about it

If I were you I would be concerned!!! Mine use to do the exact same thing, On Feb 19th at 84008km while driving at about 90km I notice the oil pressure gauge needle twitching around its normal 275 mark. All of a sudden it starts to drop all the way to ZERO!! Then a stupid orange gauge picture lights up and the DIC says "STOP ENGINE":duh:. That was the LAST time that engine ran!!!! Major damage to motor done. few crankshaft bearings, camshaft damage and block damage near lifters. Seems to me the oil was being consummed more and more as time went on. BE CAREFUL!!

JFSebastian
03-06-2010, 07:22 PM
At 101,000 miles, and I have never had oil consumption between 9,000 mile oil changes with 5w-30 Mobil 1 oil and Mobil 1 filter

Denali n DOO
03-07-2010, 11:55 AM
Hi all,

You all are going to love this...

Bought my 2006 Saab 97x a year ago, it was my first GM vehicle.

It had 35k miles when i bought it, and actually was burning oil then...

At 48k miles took it to dealer and described problem, they suggested an oil consumption test done under warranty, but i had to pay for the oil change...

Took it back at 49800 miles and guess what? it was 2 quarts low!

My schedule does not allow frequent trips to the dealer so i wnt back to have this issue taken care of at 54k...

To be told by the new service manager that my car is out of warranty and that 1 Qt. every 900 miles is NORMAL!! I showed him the service advisory and the manual where it specifically states 1 Qt. every 2k miles...

Was referred to Saab and they said the dealer had denied my claim and that there was NOTHING I COULD DO!!

IT seems that there are so many with this issue, a class action lawsuit is in order. Please respond to me if there is any interest in this as I will be suing anyway. My first and Last GM vehicle. POS!! :hissy:

My 5.3 eventually failed last month at 84000km! My dealer replaced with a New 5.3 Engine and even put me in a GMS Sierra 2500 hd for 11 days because I needed a tow vehicle for snowmobiling while my Envoy was serviced. :D. This was only my second visit to this dealer since mine was one that had to close. Second visit and they treat me like i been there for years. Wow, hats off to the GM Dealers that go above and beyond:tiphat!!!

etperez22
03-07-2010, 12:38 PM
Mine 2006 Denali was doing burning up oil Since i purchased it February 09. Back then it ws burning up a little under a 1quart every 2000 miles. On my first oil change from the dealer I mentioned that it was burning up oil. They told me to keep a eye on it and if it gets worst some actions will needs to be taken.

Well i did more than keep an eye on it. I kept a weekly journal of when I checked the oil, where it oil was at acording to the dip stick, added oil if needed, the miliage, and any service that has been done. Gave the a copy of the spreadsheet that i made to the dealer everytime I went it for service.

A little over a year later we analyzed the data it I was started to burn a 2.87 quarts every 2000 miles. One week ago the dealer took action and replaced the PCV baffel under the valve cover. I can say is so far so good. Usually I would see the oil level drop down to just above the 2nd hole mark on the dip stick. Now it is still showing full.

atv hauler
03-07-2010, 12:52 PM
If I were you I would be concerned!!! Mine use to do the exact same thing, On Feb 19th at 84008km while driving at about 90km I notice the oil pressure gauge needle twitching around its normal 275 mark. All of a sudden it starts to drop all the way to ZERO!! Then a stupid orange gauge picture lights up and the DIC says "STOP ENGINE":duh:. That was the LAST time that engine ran!!!! Major damage to motor done. few crankshaft bearings, camshaft damage and block damage near lifters. Seems to me the oil was being consummed more and more as time went on. BE CAREFUL!!

That sucks,You had the valve covers replaced right? Did not help?

Denali n DOO
03-07-2010, 01:59 PM
Yep , thats right, valve covers were done!!! My friend has 07 Avalanche LTZ with 5.3 and his has been burning oil as well. His Dealer looked at that valve cover bulliton and chose to do valve seals. So far his has been good. Like the post above says I truly believe the oil comsumption gets worse as time goes on. Would there not be a "low oil" light on the Trailvoy with 5.3? The Avalanche has one but I never saw one in my Envoy. I'm very happy with the outcome, a New Motor, the cost to Remove the motor and diagnose and put in the new one was, 23 hours labour, total invoice cost was $7568.87. Thanks goodness for extended warranty:thumbsup:!

atv hauler
03-07-2010, 05:56 PM
I have 112,000km on my 5.3 and it uses about 350ml in 3,500km(55 hours).I can live with that , I check it twice a month. In the summers months when we haul the race quad , I mostly run in the trans. in drive so I thought it would consume more but it does not change.

jwh463
03-12-2010, 11:59 AM
well I finally took mine in; clogged pcv baffle. I am relieved if this fixes my oil usage issues

Costs:


Replace driver side valve cover $286.54
1.00 1 VALVE COVER 151.54

Remove intake and clean oil residue, clean throttle body, clean pcv system $326.08
1.00 APF POWER FOAM CLEANER 11.08

I am not doing the intake thing, I think it will burn off the residue...correct? Maybe some sea foam
Let me know guys


UPDATE:
I loaned my wife the Corolla for the day while the Envoy was being repaired. On her way to pick me up from work....another woman runs a stop sign and hits my Rolla. It sits in the garage un-drivable, the rear wheel is bent and tire is flat

atv hauler
03-13-2010, 11:32 AM
I hope it works. Keep us updated

tony2006
03-18-2010, 09:23 PM
now that you have got this fixed how is it doing? Also when you first shut it off after driving and you check the oil level, have you ever tried to recheck it the next morning before firing it up? Did the oil level appear to be higher the next morning? If is draining down slow the dealer mechanic said it may be because of sludge build-up. Sludge build up can be caused by plugged baffles. Earlier in the 5.3,s life they had this problem and made a change to the baffle hole size. Please keep us up to date. thanks

quag421
03-22-2010, 08:09 AM
Man, I followed up on this post I started a while back and some good info. My oil consumption has not gotten worse, but still happens. One point as the above post says, I do notice the oil drains very slow. I generally give it at least 15 minutes to get an accurate read.

I am getting close on my extened warranty, I am going to see if they will do anything about the PVC baffel. Thanks for all the good info.

tony2006
03-22-2010, 10:19 AM
i just checked mine after waiting all night and it was the same as when i checked it last night after waiting a half hour. Someone mentioned piston rings (blow by) but i don.t know now. I will change mine again this week and will use 10-30 and monitor it from then. I will update thread as info becomes available. Good luck with yours.

jwh463
03-22-2010, 11:27 AM
well after one week and about 600miles thanx to a weekend road trip everything seems fine. I checked the oil before the trip , after I got there FULL & CLEAR & before I left to come home FULL & CLEAR. I will check it again tonight and report back. Typically oil turns dirty very quickly

I had oil changed back to Mobil One 5/30; was advis:undecideded to change oil again after 1000 miles. Dont know if I will, I will monitor and if oil appears very dirty I may change again.

tony2006
03-22-2010, 12:08 PM
great to hear your oil is staying clean. I,d change it after 1k just in case something migrated to the pan. Cheap insurance after all you went thru. Keep us posted

slikb1122
03-24-2010, 10:24 PM
The 5.3l is suppose to use about a quart of oil for every 2000 miles the vehicle is driven. This happens in every one I have ever seen or owned. Dealer will tell you the same. Some even use 1 quart every 1500 miles but is uncommon. You should check your oil every time you fill your gas tank

RedEnvoyDenali
03-25-2010, 01:17 AM
I'm not sure where the "supposed to use" comes from (I think the dealers are covering their tushes) but I just checked mine and about 1/2 quart in 2400 miles. This has been the norm for me, about 1 quart between oil changes or so.

WOOLUF1952
03-25-2010, 01:26 AM
I believe it would be better to say that GM calls 1 qt. every 2k as acceptable. It is not "supposed" to use any oil. :m2:

jwh463
03-25-2010, 01:18 PM
The 5.3l is suppose to use about a quart of oil for every 2000 miles the vehicle is driven. This happens in every one I have ever seen or owned. Dealer will tell you the same. Some even use 1 quart every 1500 miles but is uncommon. You should check your oil every time you fill your gas tank

mine was using 3 qts in 2500-2800 miles

RClark00
04-10-2010, 11:20 AM
The 5.3l is suppose to use about a quart of oil for every 2000 miles the vehicle is driven. This happens in every one I have ever seen or owned. Dealer will tell you the same. Some even use 1 quart every 1500 miles but is uncommon. You should check your oil every time you fill your gas tank

Thanks to this forum/thread... I no longer think I am crazy. The guys at the dealership made me think that I was. They change my oil EVERY time... and they asked ME where it was going. Heck if I knew, b/c the gauge has always been fine and there has never been leakage on my garage floor.

I'm now checking often and adding about a quart between changes.

jwh463
04-12-2010, 06:02 PM
1200 miles since baffle was serviced/replaced and no oil usage...all is good here

jwh463
04-19-2010, 10:47 AM
1600 miles since the baffle/valve cover was replaced. I had the oil changed again and I was down 1/4 of a quart:). I changed to Pennzoil Ultra and will keep you updated.

abner
04-24-2010, 11:44 AM
oil changes are cheap
replacement of 5.3 dod lifters are not
replacement of 4.2 cam phasers are not
both of these are effected by oil sludge from too long of oil change intervals, cheap oil, or cheap filters the oil life moniter is a easy way to spend lots of money on engine repairs

at work on monday I get to pull the heads on another 5.3 dod to replace lifters

jwh463
04-26-2010, 12:09 PM
Abner are you telling us to follow the OLM or simply the mileage? Curious about your thoughts, I drive till the OLM says 25% because I think it goes too long

marty658
04-27-2010, 10:36 PM
Hi Everyone. I am looking at getting a Denali, but the discussion about the oil consumption here, has me worried. I went out on the web and found that the 5.3L has an oil consumption issue in many GM applications. In my search I came accross this website that talks about nicks in the valve stem, and how the mechanic is supposed to diagnose and fix the defective valve stems

http://www.nastfenews.org/index.php?option=com_content&view=article&id=77:excessive-engine-oil-consumption-in-certain-gm-trucks-and-suvs&catid=52:service-information

I also found some more info at www.carcomplaints.com

Needless to say, none of the info makes me want to go out and buy a Denali with a 5.3 at this point.:(

91RS
04-27-2010, 10:52 PM
Hi Everyone. I am looking at getting a Denali, but the discussion about the oil consumption here, has me worried. I went out on the web and found that the 5.3L has an oil consumption issue in many GM applications. In my search I came accross this website that talks about nicks in the valve stem, and how the mechanic is supposed to diagnose and fix the defective valve stems

http://www.nastfenews.org/index.php?option=com_content&view=article&id=77:excessive-engine-oil-consumption-in-certain-gm-trucks-and-suvs&catid=52:service-information

I also found some more info at www.carcomplaints.com

Needless to say, none of the info makes me want to go out and buy a Denali with a 5.3 at this point.:(

I wouldn't even worry about that. All you're going to find on the internet is the bad things because people get all crazy when they have a problem and go tell everyone they can about it but never say a word about the good. They made tons of these motors, honestly you can't expect a few out of the bunch not to have some problems. My mom's Tahoe 5.3L with 98k miles doens't use any oil, my dad's 6.0L Sierra with 140k doesn't use any until its about ready fo an oil change (it may not use any more since I replaced the leaking oil cooler lines), and my uncle's 5.3L Silverado with 33k doesn't use any oil either. Consider how many people on this site have 5.3Ls and how many actually posted in this thread saying they have this problem.

digital568
05-11-2010, 11:48 PM
I have a 2006 Buick Rainier 5.3 Liter and mine has been burning oil as well. It has about 60k miles on it. It has been burning about a quart between my 3k oil change. I have had both regular oil and it now has full synthetic. It has been "losing" oil since I have had it.

Lee614
05-12-2010, 02:20 PM
I read (somewhere on this board) that there is some internal rail with holes and if it gets clogged, the engine will 'burn' oil and gas mileage will drop.

jwh463
05-13-2010, 04:19 PM
I read (somewhere on this board) that there is some internal rail with holes and if it gets clogged, the engine will 'burn' oil and gas mileage will drop.
This is the internal baffle..GMs new PVC that is in the driverside valve cover. Gets clogged and the valvecover has to be replaced

lynch55
05-13-2010, 04:47 PM
This is the internal baffle..GMs new PVC that is in the driverside valve cover. Gets clogged and the valvecover has to be replaced

:raspberryPCV-Positive Crankcase Ventilation PVC is a plastic. I know I know, but I couldn't help it!:bonk:

vap8900
10-12-2010, 06:30 PM
Hi All,

I am reviving an old thread. I am having this issue on my 2007 GMC Sierra. This started around 40,000 miles and seem to be getting worse. I have a few questions for anyone who may know -

1 - Is this covered under the 100k mile powertrain waranty?
2 - Is there any way of getting this resolved without having to complete the oil consumption test? my work and travel schedule does not allow me to get to the dealership every 1k miles, and i'm usally in the mountains or farmland when my "oil level low" light comes on.

Thanks in advance.

91RS
10-12-2010, 07:02 PM
Hi All,

I am reviving an old thread. I am having this issue on my 2007 GMC Sierra. This started around 40,000 miles and seem to be getting worse. I have a few questions for anyone who may know -

1 - Is this covered under the 100k mile powertrain waranty?
2 - Is there any way of getting this resolved without having to complete the oil consumption test? my work and travel schedule does not allow me to get to the dealership every 1k miles, and i'm usally in the mountains or farmland when my "oil level low" light comes on.

Thanks in advance.

It depends on what the repair is whether it would be covered under powertrain or not.

As far as the oil consumption test, that will depend how the dealer wants the handle it. You basically going to want to go talk with your dealer's service manager and go from there.

vap8900
10-12-2010, 07:11 PM
It depends on what the repair is whether it would be covered under powertrain or not.

As far as the oil consumption test, that will depend how the dealer wants the handle it. You basically going to want to go talk with your dealer's service manager and go from there.

Thanks. I was thinking of the PIP4574 repairs that folks have had some success with. I guess that was a broad/general question (i.e. dumb question).

billfred
10-13-2010, 09:26 PM
I just bought an 06 TB with about 55k miles. Just got back from a 600 mile round trip. I would say I lost about 1QT. Using Dino 5W30. Had some smoke from the tailpipe on cold start a couple times, but never happened again.

Oh well, I'll keep an eye on it. My old 97 F150 burns some oil too!!!:crazy:

jwh463
10-14-2010, 01:03 PM
I drove dfw to Tulsa and back and used one qt. Normal I just deal with it tired of fighting it. Driverside valve cover already replaced twice. I just started using dino and no more synthetic. It drives me crazy because my 2003 silverado with the same 5.3 motor was driven to Petaluma CA and back and I changed the oil before my son left in it. He returned four months and 4800 miles later and it was still FULL...insane.

Denali n DOO
10-16-2010, 11:22 AM
Well my oil burning 5.3 motor was replaced earlier this year after it failed and I received a Brand New 5.3 motor. The new motor is burning oil just like the oil one!!!:duh: I guess it is what it is and you just gotta keep checking the level and keep it topped up.

ce8204
10-16-2010, 04:22 PM
Ok, you guys with the 5.3's- i'm trying to think of why your oil consumption continues- I understand the valve cover fix, etc- BUT - Have any of you
considered maybe restricted airflow could be the culprit?....now hear me out

I can only assume your maint habits include REPLACING AIR FILTERS regularly.

If your on this board , then this should be routine & not an issue.

I also beleive the GM air filter box is somewhat restrictive by design, which leads me to the real question,

Is anyone using a K&N type filter ( the kind where you remove the OEM box) that allows more airflow?

( I have seen many v-8 motors that had clogged air filters & high oil consumption)

Just curious........:weird:

jwh463
10-16-2010, 10:02 PM
I have the garden variety KN filter. I ran nothing but mobil one changed every 5k till I hit 65k. Then I started trying every oil under the sun to try and hoping one will not burn as much. Of course mine has been in the dealer for much of the last 90 days for other issues....see my other thread. Long story short no more synthetic

robriguez
11-22-2010, 03:39 PM
about 85k on the clock and I'm having the same issues. I get about 1/2 qt drop every week (5-600 miles/week).

billfred
11-22-2010, 05:59 PM
Yeah, I think I figured out I'm about 1 qt low every 1000 miles of daily driving.

55k miles on mine.

Asunder
11-22-2010, 06:32 PM
Yeah...My 5.3 likes to drink 5W30 Mobil 1. About a quart per 1,000 miles also. And like others, when I went to conventional (Pennzoil) 5W30 I never added between 3,000mile changes. Why this is I know not.:confused:

d_hend07LT53
11-22-2010, 07:46 PM
it is possibly an aggressive lifter as well, mine burned 4 1/4 Qrts in 3800 miles.

ouch.

my TB goes in tomorrow for the oil change to determine the fix based upon oil consumption tests

blackdenali
11-23-2010, 07:08 PM
I have an '06 Denali (5.3l) and have been using 10W30 full synthetic oil (summer only). I too have been adding 1 litre (1 quart) between oil changes as well. I had an oil change about 1000 Km's ago (600 miles) and checked it today, was down about 2/3rd's of a quart. I do a lot of highway driving but can only assume that it is being consumed during acceleration?
My mechanic told me that there was some residual oil at the bottom of the engine (at the back towards the tranny), but I have never seen any oil on my driveway? I will keep my eye on it, but next time you get your oil changed check for a leak in the place where they found mine. Hope this helps?

playstrings
12-05-2010, 10:15 AM
:coffeeNote to Our buddy up above - with the 5.3 the odd one does NOT use oil. First I had the micro crack leaking head thing - after warranty and during bankruptcy of GM - SOL. Put in a rebuilt with new heads... using oil but it is PCV related - if I change it out it improves for a while - but still really eats it on long highway trips...

Strange thing , my daughter has a 2002 Toyota highlander - same problem - change out the pcv and it gets better. On hers I think the PCV is too small and gets gummed up.

On mine, I buy cheap oil and change it more often... and always carry a litre LOL LOL.

I now have 65,000 km on the rebuilt and it runs strong and eats oil LOL. At least with oiling the body is in good shape cause I have rebuilt engine , A/C, Alternator , Front suspension , 3 wheel bearings, fan clutch , 4 ignition switches , wiper sensor, rear wiper motor.

LOL - next summer I will work a little more on the oil vanishing mystery - so long as it starts at 30 below we are good....

Enjoy
Rick

:coffee

blind_eagle
12-06-2010, 04:55 PM
yes, mine has been consuming Mobil 5000 5w30 also. More recently it has been more noticeable (2.5qts for 5000 miles). I am at 81,000 and am chasing the P0420 code now.

Throttle body/MAF have been cleaned 2 weeks ago and last week changed the o2s on the effected Bank 1.

--It's baaaaack :mad:

Next step I am thinking is checking/changing the plugs and maybe checking the PCV drains??

I really want to see what may be the cause before replacing the Cats and foiling new ones.

jwh463
12-23-2010, 10:46 AM
I don't want to pronounce it fixed but I just drove from Dfw to Cape May NJ for the birth of our first grandchild. Did it in just under 22hrs driving straight thru. I typically drive 75+ on these extended highway runs. I drove a whole tank of gas with cruise set at 85. This is where the oil disappears quickly.

Everyone on here has read how we have experimented with different oils trying to lessen the disappearance of oil and have found no difference. Normally we use a qt every 1200 miles. I needed a qt before we left and I added one quart of Lucas synthetic oil stabilzer instead of oil based on recommendation of a friend. Much to my surprise as I checked the oil along the way I noticed I needed to add no oil. After we arrived I checked and we are down 1/2 qt. So I think I will start adding a qt of that stuff at every oil change..couldn't hurt

billfred
12-23-2010, 01:38 PM
Interesting.

Im in the same boat. I use about a qt every 1500 miles. Definitely see more consumption on long, high speed trips.

Im currently using regular dino oil. Does this stuff work for regular oil or only synthetic?

jwh463
12-23-2010, 03:47 PM
Interesting.

Im in the same boat. I use about a qt every 1500 miles. Definitely see more consumption on long, high speed trips.

Im currently using regular dino oil. Does this stuff work for regular oil or only synthetic?

I am running a synthetic blend now. There website says you can mix with either

portega
12-29-2010, 01:57 PM
I just joined this fourm and ran across this thread. I am also having oil consumption issue on my TB. I also have the issue on my 2000 Silverado with the 5.3 V8. I have just been living with the issue and adding oil when needed. I found when I did alot of high speed driving they both use more oil.

SSportWagon
01-31-2011, 05:50 PM
I'll throw my hat in the ring too ... Mine has just turned 45K. I cant really say how often/how many miles per quart needed because I really dont drive much during the week (1 mile to / 1 mile from train station per day plus local shopping trips) ... some weeks are more than others but it seems whenever I check Im just about 3/4 quart low. I'm checking more often these days ...

... and I think the short trip driving is as bad as long hauls. We take the XUV on several vacation trips per year and I also use it to tow my show/race car usually 2-3 times a year - those trips are usually 1500-2000 miles. On those trips I check it often and usually burn at least a quart before returning home.

I think it SUX that there are about a zillion 5.3's out there and GM is doing nothing about it.

fasst1
04-18-2011, 08:06 PM
Hi, I am in a horrible position I am burning about 1qt every 500-600 miles. The dealer has doen an upper engine replacement and than they replaced oil rings a few weeks later. It has not fixedthe issue at all. If anything it has gotten way worse.

We keep going thorugh oil consumption charts after they do work. They keep doing oil compression test that dont show anything.

Thank god the extended warranty has paid for this work but really still need it fixed.

playstrings
04-18-2011, 09:27 PM
OK - I know it sounds trivial - but did the put a new PCV? I find these things get gunked up easy.

bromanjr
04-18-2011, 10:47 PM
I'll throw in my :m2:

Bought a used 2004 Envoy, 164,000, maintenance history unknown.

My 5.3 used oil excessively, never calculated, but prob 1qt every 1000 miles.
I found the bulletin/recommendation and put a new valve cover on the Drivers side ($40 on e-bay) at around 168,000. Oil consumption vastly improved. When replacing the cover I noticed the engine was very sludged up. Apparently my driving and frequent oil change habits loosened some sludge and during a VERY brisk takeoff the sludge slid toward the back of the pan and plugged up the oil screen.

Instantly lost oil pressure, got the stern warning and pulled over to check. The oil seemed a quart low, maybe more. Bought a quart and put it in, was about 3 miles from home. After a restart, I had oil pressure but lower than the normal 45. I drove home and on the way it got worse. Got home a put in a second quart. Seemed better again so I drove to my service/oil change guys. The pressure got worse again the whole way. They put in some flush and conditioner (think they said it was friction modifier).

Drove home, oil pressure acceptable but still got worse as I drove. Went back the next morning for another oil change. We saw "stuff" in oil pan so a couple days later I had them remove the pan and clean it at around 173,000. (luckily only 2wd).

Well sorry for the long winded story, here is the result.
I now have slightly lower oil pressure than before the incident and cleaning of the oil pan. Sometimes I can hear some looseness (knocking) when cold. My oil consumption improved right after the cover change and still seems excessive but is more like a quart every 3000 miles or more now (at least something improved).

The truck has high miles, runs excellent, rides perfect and I plan to just maintain and drive it til something breaks, then fix it again.

sBoddie
09-04-2012, 10:26 AM
171,000,
My similar 2-year story to above ended this weekend in a stalled coast to a stop in a parking lot. Intermitent oil consumption (sometimes weeks with no perceivable loss, other times 2 quarts low outta nowhere... highway, 70mph+ for hours). Mechanic did a BG109 treatment, which seemed to help for about a year. Lately there appeared a engine top rattle when shifting @ 2300 rpm, or for a second when you lift off the throttle. No discernable tapping at idle.

Last week the check light came on, after it started idling rough. Went off and on a few times depending on whether it sat running for a while or was only driven at speed. Drove one way 5 miles. When I turned it on to go back, it is now tapping under _any_ load. A metal squeak chimes in to the beat of the tap, and gets louder. I pull it over, check the oil. It appears full, but there are fine metal flecks and maybe some water. It's a recent oil change, so it's hard to tell.

I slowly turn it back into a safe parking lot, but it stalls as I shift into reverse to back into the space. Won't turn over... starter ingages a half-turn, but won't crank. The only code is P0300 - misfire... don't know which cylinder. Mine _does_ have DOD.

Is the dead engine a traumatic culmination of all 3 plagues? Have not gotten it to a mechanic yet. :worried:

91RS
09-04-2012, 06:54 PM
Could be a spun rod bearing. Common in in the SS; not so common in the 5.3L since people generally don't drive them as hard, but it's still the same bad oil pan design. Might be time to upgrade that baby to a 6.0L or even a 6.2L! Once you get it fixed, run 6.5-7 qts of oil to prevent oil starvation. Unless you want to fix it altogether and go with a C6 oil pan.

sBoddie
09-11-2012, 07:31 AM
Mechanic says it's a fatal internal failure of some kind. Didn't seem interested in pulling a head apart to investigate. There were misfire codes for multiple cylinders... thinking crankshaft. Found a rebuilt engine, total job $7500. Not gonna happen.

Is this fixable? I can be without the vehicle quite a while if it means saving it. What should I look for if somebody's willing to rebuild?