5.3 Oil loss issues [Archive] - Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum

: 5.3 Oil loss issues


3fan4evr
05-24-2010, 03:34 PM
I have a 05 EXT with the 5.3 V8 and just got the bad news that the motor has spun a barring. This was caused by the consistent loss of oil. There were no signs of burning, leaking or any indications of loss, except for the occasional smell of burning oil. The engine would lose about three quarts between oil changes. The oil life indicator even would read 50% or better while the level was low. I just flipped 90K. From my understanding this is a GM known issue with the 2005 and 2006 5.3 motor. Itís also called Pistol slap, as the motor is started cold it knocks very badly till warmed up. I am currently trying to get GM to offer me a buyback, as I have been told from the dealer that there is a buyback program for this motor. However I do want to keep the truck and would like to swap out for the 6.0, same motor that is in the SS model. Does anyone have more information on this swap? Thanks,

bartonmd
05-24-2010, 03:44 PM
I have a 05 EXT with the 5.3 V8 and just got the bad news that the motor has spun a barring. This was caused by the consistent loss of oil. There were no signs of burning, leaking or any indications of loss, except for the occasional smell of burning oil. The engine would lose about three quarts between oil changes. The oil life indicator even would read 50% or better while the level was low. I just flipped 90K. From my understanding this is a GM known issue with the 2005 and 2006 5.3 motor. It’s also called Pistol slap, as the motor is started cold it knocks very badly till warmed up. I am currently trying to get GM to offer me a buyback, as I have been told from the dealer that there is a buyback program for this motor. However I do want to keep the truck and would like to swap out for the 6.0, same motor that is in the SS model. Does anyone have more information on this swap? Thanks,

1. The OLM is an algorithm based on mileage/load/temp/rpm/etc... It does not measure anything about the oil, and is not a low oil level indicator.

2. Good luck on the buyback! The spun bearing sounds like it was from you not checking the oil frequently enough, and running it dry...

3. it's PISTON slap, not "pistol slap"...

4. With a V8 already, I suspect the LS2 swap would be doable, but would still require completely new electronics, because the later V8 models used CAN OBDII, instead of the old style of OBDII, and they're not compatible... You would probably be the first one to do this swap, so good luck. I suspect, however, by the wealth of knowledge contained in your first post here, that this would be over your head. I would suggest getting your money from GM for the buyback (if they'll do it) and buying an SS...

Mike

ETA: FWIW, the LS2 grenades the upgraded 4L70E, so your 4L60E will need built up...

DJones
05-24-2010, 05:02 PM
Putting the 6.0 in an EXT!? That sounds like a good idea to me! Very complicated though.

n0kfb
05-24-2010, 09:02 PM
I have a 05 EXT with the 5.3 V8 and just got the bad news that the motor has spun a barring.

What are the symptoms that make you think you have spun a bearing? Has the engine been torn down?

This was caused by the consistent loss of oil. There were no signs of burning, leaking or any indications of loss, except for the occasional smell of burning oil. The engine would lose about three quarts between oil changes. >snip<

IMHO, If you knew your engine was using oil and did not check the level and top it up, you were negligent in maintaining your engine. Good luck getting GM to pay for this. :duh:

FWIW, some early 6 cylinder engines had problems with piston slap. I've not heard anything about problems with any of the V-8's

-- Dan Meyer :coffee

ScarabEpic22
05-25-2010, 12:13 AM
Guys, dropping a 6.0L would be a piece of cake. Just get either an iron block 6.0L from a fullsize truck (00-06), preferably an LQ9, retune the PCM for the increase in displacement and done. The electronics on a 5.3 -> 6.0 swap are identical, biggest thing is you cant run an 07+ motor as the crank reluctors are different (58x for 07+, 24x for -06).

1) So, either get an LS1 and stroke it to 6.0L or leave it at 5.7 or buy an 05-06 LS2 with the 24x reluctor (58x WILL NOT WORK).
2) Swap old motor out, new one will go in the EXACT SAME WAY. No difference in connectors, etc. Knock sensors might be different, might need to reuse the old ones (LS1 style) as the LS1 PCM doesnt seem to like the LS2 sensors sometimes.
3) Tune original PCM for new displacement and airflow characteristics, any competent tuner can do this easily.
4) Enjoy a 5.7/6.0L tuned V8 in your EXT.

The blocks are almost identical on the 5.3 and 5.7, LS2s are slightly different but not enough to really matter. Motor mounts, wiring (except knock sensors), intake, are all the same.

bartonmd
05-25-2010, 09:18 AM
Guys, dropping a 6.0L would be a piece of cake. Just get either an iron block 6.0L from a fullsize truck (00-06), preferably an LQ9, retune the PCM for the increase in displacement and done. The electronics on a 5.3 -> 6.0 swap are identical, biggest thing is you cant run an 07+ motor as the crank reluctors are different (58x for 07+, 24x for -06).

1) So, either get an LS1 and stroke it to 6.0L or leave it at 5.7 or buy an 05-06 LS2 with the 24x reluctor (58x WILL NOT WORK).
2) Swap old motor out, new one will go in the EXACT SAME WAY. No difference in connectors, etc. Knock sensors might be different, might need to reuse the old ones (LS1 style) as the LS1 PCM doesnt seem to like the LS2 sensors sometimes.
3) Tune original PCM for new displacement and airflow characteristics, any competent tuner can do this easily.
4) Enjoy a 5.7/6.0L tuned V8 in your EXT.

The blocks are almost identical on the 5.3 and 5.7, LS2s are slightly different but not enough to really matter. Motor mounts, wiring (except knock sensors), intake, are all the same.

Yep, mechanically, it'd be as much a piece of cake as an engine swap in one of these can be... Take apart front suspension to remove half shafts, drop transmission and T-case (or rather, move them back out of the way), remove radiator, exhaust manifolds back to the Y-pipe, etc... Have to use an LS2 if he wants to keep his 2WD, unless an iron block truck 6.0 will take the aluminum engine's oil pan??

You can either do the retuning of the original PCM and replace all the sensors, or you can swap out all the PCM wiring, etc. in the vehicle for the donor vehicle's wiring... Custom tune is manditory...

Read the OP... Would you suggest he try this by himself?

Mike