View Full Version : Need help with front differential issue.
nnolte
04-14-2009, 09:18 PM
I have an '03 TB with a 5.3L V8. I am having a serious issues with my front differential. The major symptoms are A LOT of noise and there is resistance to the TB merely rolling. The noise is worse in 4WD but still very loud in 2WD.
I removed the driver's side CV axle shaft hoping it was just a bad CV joint, but no luck. It's definitely in the front differential. I have the factory service manual and it looks like removing the front diff is a major chore. Am I wrong? Any advice? Does the oil pan actually have to be removed?
When I get the diff apart is it serviceable or am I better off just trying to find a used one to replace it? I need to match the gear ratio, right? When I spin the driver's side front wheel, it sounds like gears are grinding and not meshing. No other wheels spin (it's completely off the ground on stands).
Although it sounds hoosier, I've even considered removing the front drive shaft and CV shafts and going 2WD. Is there some sort of replacement interior/dash piece for the 4WD switch?
Honestly, I've owned GM cars all of my life and this has to be the worst auto I've ever owned. It's a repair project every two months. After this is fixed, I think I am going to sell it.
Thanks for any advice or information others can provide. I am not a TB enthusiast, just a schmuck with an expensive repair. Any insight or assistance is appreciated.
the roadie
04-14-2009, 09:28 PM
Sorry for the problem - how many miles? Were the diff oil and TC fluids ever changed? How's the level in the front diff now?
Anyway, it's a major pain, as the manual indicates. Buying a used one with the right gear ratio is a fine tactic, and not as expensive as rebuilding with GM parts prices.
And some members have even gone 2WD with those deletions. You can make a couple of bucks back selling the electrical parts. If you get to that point, I can find you the part number for the blank-up dash plate. Actually, let me just look it up now so you can take note of it: # 15289764 $8.50 at parts4chevys.com
Item #17 in this pic:
http://www.compnine.com/largeimg/050726TS16-109.gif
nnolte
04-14-2009, 09:43 PM
93,000 miles. I have topped of the diffs and transfer case, but haven't done a change.
Thanks for the part number. I am hesistant to switch to 2WD because I have problem selling the car to someone straight up without disclosing the switch, and I think a dealer would quickly discover it.
I have a tale of woe of repairs to this vehicle that I won't bore you with.
nnolte
04-17-2009, 10:24 AM
I decided not to convert to 2WD and destroy the value of my vehicle. I was tempted b/c it's so much work and (potentially) money.
After two evenings, I got the differential out and apart. Although the diff was never (visibly) leaking, it was completely dry. So it's not hard to understand why it failed. I was amazed to see that the two halves of the differential case do not use a gasket. GM probably saved $0.50 on that great idea. The car has 93k miles on it and the diff was last checked at about 80k miles. I have never heard of a diff going dry in 13k miles without a visible leak.
The pinion bearing is destroyed and so are the ring and pinion. I determined that it will be much cheaper to replace with a used diff than to rebuild mine at GM prices. The ring and pinion alone would cost about $500, let alone the pinion bearing cost and the difficulty of properly setting up a differential. A dealer quoted a complete differential assembly for $2200 (plus tax).
I have located a used one at a junk yard for $400 not too close to my home, but since I have a 3.73 axle ratio the proper diff was hard to find. Apparently most trailblazers have a 3.42 ratio. I will install it this weekend and hopefully be on the road again Monday.
This car has been one repair after another for almost 6 years. I can't believe the failures will ever stop. Might be time for a new vehicle. After a lifetime as a GM customer, this vehicle has definitively ended that run.
playstrings
08-14-2009, 08:28 PM
AMEN NN, what did you buy ??
My envoy is taking me to the outer limits TOO !:duh:
linneje
08-15-2009, 12:40 AM
I've got the same setup as you playstrings - haven't had major problems other than AC line replacement - what have you had go wrong on you?
the roadie
08-15-2009, 12:47 AM
This is an old thread, and nnolte hasn't logged in since May. Sorry.
playstrings
08-15-2009, 08:01 AM
Hey Roadie - it's funny how many are out here reading old news hahahhaa.
linneje - good to meet you....
I have 140K km - which is somewhere around 90000 miles but lots of these were at 1/2 that milage
I have either a cracked head (most likely) or blown head gasket. Known issue with specific head manufac.
I have had the cat replaced on warranty
- they replaced the fuel pump due to rotten lines (keep an eye out for this on yours) XL problem.
- I now have a bearing shot in the diff - and the fluids were changed blah blah bla from all the guys on here
- the dealers answer was to let it go and trade it out for a used diff....??? and how long will that last ???
- did a wheel bearing (warranty)
- did 4 ignitions (3 were warranty) I now carry one in the glove box
- windshield wiper control unit (real pain when no wipers in the rain) warranty
- the AWD switch is flakey - I should change that ....
- now have a good clunk in the front end which I am pretty sure is the ball joint or linkage issue
- starting to think it is a mechano project - take it all apart and put it back together again...
- oh - and I oiled this pig every year - rusting at the seems all over - I have a 95 toyota with 300,000 km that has less rust than this poorly engineered vehicle
- what you find in reading around here is there are a lot of weak links - and we are the informed trying to learn and help others - pity for all the poor folks that are getting hammered by GM
My mistake was using it mostly in the winter for tough weather - if I had drove it hard maybe the diff would and the head have been a warranty deal ... but I have never had a vehicle in my life in the shop as much as this thing .... 12 step - my name is Rick and I own a GM ... its been 30 days since my last repair ...
Too bad - when it runs good I love it - but after the diff bearing and the rust showing up - I think it is time to buy a Sequoia LOL -
However - I do have a very hard head ...:duh::bonk:
regards
Rick
nnolte
08-15-2009, 10:44 AM
My probs began with the painted plastic body panel that houses the third brake light *blowing off* while I was traveling down the road. The dealer initially decided that it would warranty the part, but then decided the flanges that it mounted to (which are permanently attached to the rear window glass) were bent. The dealer then changed its mind and said that I bent the flanges even though they are quarter inch steel and completely covered by the plastic part. How can I bend quarter inch steel covered by plastic without damaging the plastic? They didn't have an answer for that, but were sure that I did it somehow. It couldn't have been assembled that way even though the car was brand new.
They sent me home with a new painted part in the back but refused to fix the mounting issue. I had to take them to arbitration before the Better Business Bureau, which I won. To top it off, the dealer charged my credit card for the loaner car without my authorization (I paid for a paint scratch repair on the same trip). It was supposed to be complimentary for the warranty issue. I sued GM in small claims and won that money back.
After winning the arbitration, the dealer's president told me that he wouldn't repair my car, wouldn't do business with me and "would teach me a lesson." He then called my employer (he knew my boss) and tried to get me fired. My boss laughed about it, and I got the warranty repair done somewhere else. Needless to say, I don't go back there any more (ELCO Chevrolet in Ballwin, MO).
I have also replaced the front differential (big job), tie rods ends (one twice), a window motor assembly, a four wheel driver encoder switch (warranty, took three trips to the dealer to diagnose that one), leaking A/C repair when new (warranty), radiator (another big job), water pump, alternator (twice, second time under Auto Zone warranty), battery, intake manifold gaskets, sway bar end link, radiator fan clutch, and a recall repair on the rear door latches in addition to the typical maintenance fluids, belt, hoses, brakes, shocks and struts. I also love the fact that you can only buy the transfer case oil from GM (Mon-Fri 8-5 only).
All my windows have vertical scratches in them from the dew strips scratching them up (see TSB 04-08-64-012C). The fan clutch ticks like a time bomb (See TSB 05-06-02-004). The shift from 1-2 feels like someone is kicking you in the butt (See TSB 07-07-30-024 or 01-07-30-030A). So these are all known issues that others are also having.
This car has been a nightmare. I have never owned a vehicle so unreliable. Now my wife wants a GMC Acadia, and I am thinking "wouldn't I have to be an idiot to get burned again by GM?"
playstrings
08-15-2009, 11:00 AM
OMG - what arrogant idiots these dealers can be.
Hey nn thanks for your note... I knew that the reliability on these is questionable. No way I would buy another voy or tb but I have been thinking yukon or tahoe. I need to do more research I think. My other option is a Sequoia, which seems to have less headaches than the voy.
Sad thing is I need to fix it to get rid of it LOL LOL :bonk::bonk::bonk:
I would keep it and drive it but I am concerned on what comes next???
I am building the courage to go out and pull the diff now. Then I have to do the heads ..... pain in the butt....
When all else fails - close my eyes and open my wallett - tough to do when you have a teenager bleeding you dry LOL....
Enjoy the day Man !
Rick
nnolte
08-15-2009, 11:02 AM
Do you have the service manual? I wouldn't do the diff. without it; it was really helpful. Let me know if you want me to send you the appropriate pages in PDF.
playstrings
08-15-2009, 11:04 AM
Hi , no service manual but I do have an Aldata subscription. How much was the manual? Where did you get it? Thanks
playstrings
08-15-2009, 11:06 AM
The PDF's would be much appreciated - did you do yours yourself ? How long did it take ? What would you do different? Would you do it again LOL?
nnolte
08-15-2009, 11:21 AM
I'll get the PDFs for you. Check back later today. It was a big job and an impact wrench is a major help. I took two evenings of about 3 hours each to get everything apart (by myself) and one whole Saturday to put it back together with a helper.
I have never done the heads, but the intake manifold gasket repair wasn't that hard. Most of the time was spent trying to locate the proper tool to remove the fuel lines from the injector rails.
playstrings
08-15-2009, 11:25 AM
Did you do the intake gaskets cause of a coolant loss ?
Did that solve the problem ? My tech figured the intakes could not be the problem and it had to be the heads or head gaskets.
Could you see the failure in the intakes ? What special tool did you need?
Thanks for your help Man - crazy what info you can find out here.....
You have the 5.3 right ...
Thanks
Rick
playstrings
08-15-2009, 11:28 AM
LOL - I have air and lots of tools - some days I just need courage and a young buck friend of my daughters to lay on the floor for me lol....
the roadie
08-15-2009, 11:34 AM
- some days I just need courage and a young buck friend of my daughters to lay on the floor for me lol....Careful with the kinky stuff on a family forum! :crackup:
playstrings
08-15-2009, 11:38 AM
:woohoo:
You left coast guys ...... hmmm..... :nono:
But while your hear - While I am tearing at this diff - what else should I change just cause I am there at 90,000 mi ??
Upper Ball joints are hi on my list - any links weaker than average ?
Thanks
nnolte
08-15-2009, 11:40 AM
My intake manifold was leaking vacuum and causing troubling codes indicating the mixture was too lean. I can hook my laptop up to my car to see what the sensors are seeing, and I was getting the lean condition even though the computer was going to full rich.
After checking the MAF sensor to make sure that it was good, I figured it was the intake gaskets because they are always a major problem on these American cars with plastic intake manifolds. I tried just tightening the bolts first, but that didn't help.
Didn't have a coolant problem.
linneje
08-15-2009, 12:16 PM
Wow, sounds like you are both having a boatload of problems. I think that it could be more of a bad build than a bad design necessarily. It is true, though, that repairs cost more with this vehicle than with, say, my Chev Venture. That is where this site is invaluable, as they can help cut down on repair and maintenance costs.
I still believe this Envoy is the nicest vehicle I have ever or probably ever will drive, though. We have the heated leather seats, DVD Bose system, tow package, load leveling, etc. and it rides really smooth.
nnolte
08-15-2009, 12:19 PM
Here are the docs you'll need to do the heads and the differential. Let me know if you are missing any instructions.
You don't really need the special tool they mention to remove the shaft that runs through the oil pan between the diff and the intermediate shaft bearing assembly on the other side of the oil pan from the diff.
For the diff: http://ftp.pwp.att.net/n/e/nelson_nolte/diff.pdf
For the heads: http://ftp.pwp.att.net/n/e/nelson_nolte/heads.pdf
I got my factory service manual on EBay. It's on a DVD data disk. http://cgi.ebay.com/ebaymotors/02-03-04-05-Chevy-Trailblazer-Repair-Manual-Factory-OEM_W0QQcmdZViewItemQQ_trksidZp3286Q2ec0Q2em14QQha shZitem45ed97b728QQitemZ300338886440QQptZMotorsQ5f ManualsQ5fLiterature
nnolte
08-15-2009, 12:30 PM
I don't understand when people say "bad build." These sub-assemblies are made by different contractors in different plants and merely assembled to one car by different people along the line. The problem is poor quality. I am glad to hear your Envoy is doing well, but there is no denying that what I and others are suffering from is an overall lack of vehicle quality.
I ALWAYS purchased American until this car. I think I am the last person on the planet to acknowledge that the Japanese focus more on quality than the Big Three. However, I bought a Japanese car 18 months ago and nothing, not even a rattle, has happened in 20,000 miles. That's a lot more than I can say for my last four GM cars.
linneje
08-15-2009, 03:12 PM
It does vary because of where the vehicle is manufactured (I believe). For example, I have read countless problems with Chev Ventures and the intake manifold gasket. I have three friends with the Venture, and none of us (even into 200,000 K) have had this problem. I would guess they used a different part here in Canada because of a different supplier. Like you would find Impreial size bolts on the American builds, and we find metric on the Canadian builds.
I agree there are some things that are bad design (like the exposed A/C line near the rear tire that gets pelted with rocks) but I would be careful about thinking NA vehicles have the market cornered on that. I wont bother you with the nightmare of my friend's import minivan.
nnolte
08-15-2009, 03:30 PM
The bolts on American vehicles are metric as well. No one designs a car entirely for Canada. :)
the roadie
08-15-2009, 04:37 PM
Like you would find Impreial size bolts on the American builds...Indeed. I better unpack some English wrenches I haven't used in 20 years. :undecided
linneje
08-15-2009, 06:28 PM
I had no idea. I thought you americans were stuck on the imperial system in everything.
Chickenhawk
08-15-2009, 06:50 PM
Didn't you catch the news last week? Obama decided to postpone President Bush's metric reform act for the transportation network because the motor vehicle industry objected.
Apparently, they just didn't like Bush's "graduated reform system" where the U.S. converts over to the British system of driving on the left side of the road, but instead of doing it in one quick go and potentially confusing drivers, Bush wanted to gradually move to the initiative, with trucks and buses driving on the left by 2012, and cars by 2014.
I can't understand why anyone would protest this. It seems quite reasonable to me ...
playstrings
08-15-2009, 09:58 PM
Hey NN,
Thanks for the notes bud !! Great help....
:coffee
playstrings
08-15-2009, 10:09 PM
Hey Linneje !!
Wait till the gremlins arrive....
When this thing is running smooth - it is a cadillac on a frame....
I love it, that's what makes me crazy... the engineering short comings are management travesties....
All of a sudden you will be spending big coin if you can't do it yourself.....
Bask in the sun and enjoy the quiet ......
And save a few for that gremlin day lol....