Just purchased a 1995 2500HD for an additional work truck. The thing was skipping on #5 and a compression test showed what I pretty much knew. Time for a valve-job. Pulled the intake and lo and behold it's sludged. A valve-job just turned into an engine overhaul. Well, I was looking on Amsoil's webite for a filter for it and they have a note about the 5.7 being a sludge-prone engine and they advised factory service schedules. The fella I got the truck from swore he did his oil changes and based on the lack of wear on rocker arms,mains,cylinder walls I believe him. Anyone else had an issue with a late-model 5.7L making dino-preserves in the engine? Goo thing parts are relatively cheap for these old things.
5.7L Chevy is a sludger too??
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Originally Posted By: addyguy
Some 5.7's suffer from IM gasket failures, I think, and THIS is what causes sludging - slow coolant seepage into the oil.
I don't think the engine design makes it a 'natural sludger', like Toyo 3.0's and the like.....
Perfect answer. Spot on!
Some 5.7's suffer from IM gasket failures, I think, and THIS is what causes sludging - slow coolant seepage into the oil.
I don't think the engine design makes it a 'natural sludger', like Toyo 3.0's and the like.....
Perfect answer. Spot on!
The old 350 design is not a known sludger,Ive had 4 with no issues.What about the owner before him?,it is possible also to have zero wear problems on these engines despite oil abuse.I would debate the need for overhaul unless oil consumption or rods making noise is obvious.
Originally Posted By: FL_Rob
The old 350 design is not a known sludger,Ive had 4 with no issues.What about the owner before him?,it is possible also to have zero wear problems on these engines despite oil abuse.I would debate the need for overhaul unless oil consumption or rods making noise is obvious.
He was the original owner. No coolant ingress into the engine. It's getting an overhaul. Not about to spend the time trying to patch a sludged-up motor.
The old 350 design is not a known sludger,Ive had 4 with no issues.What about the owner before him?,it is possible also to have zero wear problems on these engines despite oil abuse.I would debate the need for overhaul unless oil consumption or rods making noise is obvious.
He was the original owner. No coolant ingress into the engine. It's getting an overhaul. Not about to spend the time trying to patch a sludged-up motor.
Naw those are not sludgers. Coolant leaks, short trips or a stuck open T-stat will make sludge in any engine.
How many miles on this 15 year old truck?
I have sludge in mine, but that was with inconsistent/ too long OCIs.
This will be the third late-model(1990-up) 5.7L I have overhauled in the last few years. All of them were full of hard crusty sludge. I just assumed it was neglet but Amsoil's reccommendation sheds a different light on it.
As someone who has killed DOZENS of 5.7's in brutal service, the sludge thing is a pure neglect issue.
Originally Posted By: addyguy
Some 5.7's suffer from IM gasket failures, I think, and THIS is what causes sludging - slow coolant seepage into the oil.
I don't think the engine design makes it a 'natural sludger', like Toyo 3.0's and the like.....
Agreed- its much like the 1990s Dodge 5.2 and 5.9. Engines that had existed for decades and were SUPER easy on oil were suddenly throwing crankcases full of grunge. In the Dodge case, it was an intake plenum gasket allowing mixing of crankcase air and air/fuel mix (and exhaust gasses in the case of EGR engines) In the Chevy case, it was a change to intake manifold gasket. In either case, its fixable but still an aggravation.
Some 5.7's suffer from IM gasket failures, I think, and THIS is what causes sludging - slow coolant seepage into the oil.
I don't think the engine design makes it a 'natural sludger', like Toyo 3.0's and the like.....
Agreed- its much like the 1990s Dodge 5.2 and 5.9. Engines that had existed for decades and were SUPER easy on oil were suddenly throwing crankcases full of grunge. In the Dodge case, it was an intake plenum gasket allowing mixing of crankcase air and air/fuel mix (and exhaust gasses in the case of EGR engines) In the Chevy case, it was a change to intake manifold gasket. In either case, its fixable but still an aggravation.
i've seen a 5.7 sludge like no other a guy ordered a reman engine and the core he brought in was thick with sludge, but i think it was neglect or maybe a coolant leak
Would all this apply to 305s too? I do know GM never get intake sealing right in the 1990's and 2000's.
None of these engines are known sludgers i owned tons of them over the years..IF there is a build up it's a maintenance oil neglect thing.
Well, if that's the case, why is Amsoil calling it a sludge prone motor? The intake leaks were prevalent in the 5.7L Vortec engines with the plastic intake manifolds. The earlier 5.7s with the aluminum intakes did not have high failures of intake gaskets.
All engines will sludge with lack of maintenance but you don't call it sludge-prone for that reason.
All engines will sludge with lack of maintenance but you don't call it sludge-prone for that reason.
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Originally Posted By: jdog
gm realy mesed up whin they stoped using the good old 350!
Why? The LSx family is better in every possible way.
gm realy mesed up whin they stoped using the good old 350!
Why? The LSx family is better in every possible way.
From a cost-to-repair standpoint the 350 was better. I think long-term durability goes to the LSx engine family.
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