WallaceR

Hey guys I'm new to this form but I really need some advice about where to go from here. I have a 09 Chevy Silverado 1500 5.3L. 6 months ago my lifters collapsed, sent my truck to a mechanic and let's just say it was a nightmare. The initial repair was done in 3 weeks I pick the truck up and pulled off the lot and it was still doing the same thing just not as bad. So I take it back and he agrees to fix it and 5 months later and a lot of arguing and things in between I get it back.(let's just say I will be taking actions on this whole situation) but... It seems to be fine now but I need to know where to go from here. The cylinder head gaskets were replaced, DOD lifters replaced, oil and filters and I think that's it. I was told the cam wasn't damaged but I really don't believe anything this guy says after everything that happened. I've read a lot about AFM disablers and they seem to be the way to go but I've also read that is not for high-mileage trucks. Do any of you guys have any knowledge or experience firsthand with having an AFM disabler or what to do or not to do from here. THANKS