Don't always trust your mechanic, fixed my "blown" engine for $7.

[tights24]

One final question if you don't mind. Forgive my ignorance, but what determined the valve cover upgrade? Was this a recall, TSB, something else? Any idea where they retrieved that info from? Thank you sir.

 

[wsteele]

One final question if you don't mind. Forgive my ignorance, but what determined the valve cover upgrade? Was this a recall, TSB, something else? Any idea where they retrieved that info from? Thank you sir.

The GM Technical Service Bulletin addresses fixes for problems induced by a couple of design flaws.

GM determined that engines that had the down rev valve cover (mine was a 2007, so had the original valve cover design) and lacked a deflector on the AFM pressure relief valve could suffer issues with carbon buildup in cylinders, sufficient to cause stuck rings and lead to a downward spiral of oil consumption. The TSB addresses the steps the service techs should take to fix the issues, up to and including replacing the pistons and rings. I think the piston and rings replacement was likely only used in the most extreme cases where de carbonization failed to free the rings. Mine was such a case. I think mine likely ended up that way because I used my truck to tow a pretty heavy trailer frequently in the first 60K miles in the hilly country of the west (tow mode higher rpms being SOP).

The dealer said GM would cover the parts for an engine under 100K miles.