Howdy everyone. About two months ago I had the dreaded AFM lifter failure on a 2015 Sierra 1500 SLT L83 with only 55,000 miles. Number 7 exhaust stuck, but there was no camshaft damage thankfully. Price to replace both banks (was advised by the foreman that this was the way to go) and the manifold was $5400. GM was "nice" enough to pay 38% of this, bringing my price to $3400. They also didn't have any of the manifolds in the entire country at the time, so my truck sat in a dealer bay for one month. The work came with a two year warranty for this issue.
Anyway, I have been driving it and it is mechanically fine now (the radio screen is doing the glitchy channel/screen changing business, but I guess that is for another thread). The dealer shop foreman advised that he had done about 50 of these in the last 7 years. In fact, mine was not the only one sitting in there waiting for a manifold. He advised the Range AFM delete and running 5w30 oil instead of the manufacturer recommended 0w20. He said that the Range delete should stop the AFM lifters from actuating as long as the module is plugged in, and that although it would not technically stop failure of a non afm lifter, these failures were much less common than the AFM lifter failures.
I have not yet bought the Range module. I really like the truck, but don't want to be responsible for a $8000 repair two years from now if another lifter takes a dump and takes the camshaft with them. I don't think GM will help much, if at all at that time. I am wondering if anyone with intimate understanding of the issue can comment as to the reliability post repair if the Range AFM disabler is used.
I would like to continue to drive the truck but am getting tired of pissing away money at it. In the last six months I have had this, the known AC coolant leak, the brakes needed replacing, and now after picking the truck up last month the screen is acting glitchy and will be $1300 to replace it with no guarantee that it will fix it for good.