mnemonicmark
TYF Newbie
- Joined
- Mar 1, 2023
- Posts
- 3
- Reaction score
- 1
Good morning, everybody!
I have had my vehicle back since Friday. It runs well. No more noises, or shaking of the engine/exhaust system. Have driven 100+ miles over the weekend — all is well. (knocking on wood...)
@Geotrash: The mechanic told me the lifter failed because of poor hardening of the roller bearing in the lifter. At least that's GMC's theory/explanation. My question, how metal that is not hardened properly then caused damage on a hardened camshaft remains unanswered... Unless the camshaft also was poor metal.
The mechanic also offered his personal opinion: Poor lubrication and failure to do oil changes frequent enough and on time during the first 40-50k miles of the vehicles life. I bought it at 48k.
Several mechanics have now told me that they recommend oil/filter changes after ~4k miles - no matter what the oil life algorithm shows/calculates. In addition to that also checking that proper oil levels are always maintained — if the car burns oil. Even the smallest amounts of oil being used/burned means it compounds towards any — and in particular — longer-life oil cycles.
WalleyMikeIII: It was indeed the passive lifter on cylinder 3 that failed. Given the problems we know of with AFM/DFM that was a surprise. The fact that GMC (after some pressure) agreed to change all lifters — even if only one lifter had failed — suggests to me that there indeed could have been a manufacturing/specification problem with the lifters of a certain generation or a particular manufacturer.
I'm going on a 3000+ mile road trip next month and that should put the repair job and the new parts to a test. I'll update here again at some point.
/M
I have had my vehicle back since Friday. It runs well. No more noises, or shaking of the engine/exhaust system. Have driven 100+ miles over the weekend — all is well. (knocking on wood...)
@Geotrash: The mechanic told me the lifter failed because of poor hardening of the roller bearing in the lifter. At least that's GMC's theory/explanation. My question, how metal that is not hardened properly then caused damage on a hardened camshaft remains unanswered... Unless the camshaft also was poor metal.
The mechanic also offered his personal opinion: Poor lubrication and failure to do oil changes frequent enough and on time during the first 40-50k miles of the vehicles life. I bought it at 48k.
Several mechanics have now told me that they recommend oil/filter changes after ~4k miles - no matter what the oil life algorithm shows/calculates. In addition to that also checking that proper oil levels are always maintained — if the car burns oil. Even the smallest amounts of oil being used/burned means it compounds towards any — and in particular — longer-life oil cycles.
WalleyMikeIII: It was indeed the passive lifter on cylinder 3 that failed. Given the problems we know of with AFM/DFM that was a surprise. The fact that GMC (after some pressure) agreed to change all lifters — even if only one lifter had failed — suggests to me that there indeed could have been a manufacturing/specification problem with the lifters of a certain generation or a particular manufacturer.
I'm going on a 3000+ mile road trip next month and that should put the repair job and the new parts to a test. I'll update here again at some point.
/M