If there are other wear issues they should notice them when then tear down for valves. So if it gets worse they will have to rebuild more or replace motor ...

If there are other wear issues they should notice them when then tear down for valves. So if it gets worse they will have to rebuild more or replace motor if it's more economical.

Exactly, but shouldn't something have caused the bad valves or can they just go bad on their own. I know it will all get fixed by GM but just curious how it would have happened.

Glad to hear you are getting it fixed under warranty. As far as the valves being bad, did they mean the valve lifters? They (lifters) can go bad for a variety of reasons (eg: poor oil flow or pressure to them, not changing the oil on schedule, Etc.).

I'm guessing lifters, but I know it wasn't oil changes because I never let the OLM get past 25% and I use AMSOIL OE 5w30 oil with a mobil 1 extended performance filter. If it was oil pressure related my dummy light never showed up, so I'm just curious how this could have been avoided unless it was just bad parts from the factory or after time it became out of tolerance. I wish my truck had some way to actually see the oil pressure instead of a dummy light. But I'm guessing the oil pressure sending unit is in the same spot for the dummy light and the actual gauge, so maybe that would not have helped?

Well, I always use an abundance of caution and change my oil at three thousand mile intervals. I know, it's old school, but It has worked well for me. I don't care how good a quality of oil you run (I would always reccomend a good quality oil), the oil itself can not prevent how much contaminent get in it. The oil may be still "good", but if it's got contaminents in it, that can cause problems (such as clogging up oil passages or wearing metal/bearings to beyond acceptable toilerances).

Would you suggest hooking up a oil pressure gauge on the a-pillar like an autometer electric motor or a mechanical gauge. And what do you mean by contaminants: do you mean water, metal shavings, and other stuff that shouldn't be in it. If it means saving my engine I'll start changing it every 3,000 miles, but Ill have to switch to Mobil One full/syn instead of AMSOIL that stuff is too expensive to change out every 3,000 miles. I'll talk further with my dealership to see if they can give me a better understanding on why they think the engine has to be rebuilt at only 53,000 miles.

I'm talking about the by-products of combustion, condensation, small particles that wear off of the moving parts inside the engine, Etc. I'm not saying everyone has to change their oil every three thousand miles, just that's what I do and it's worked great for me. I'm not even saying that the way you service your oil was what caused your engines problem. I have heard great things about Amsoil and I have friends that swear by it, but, the main reason I have never used it is because of it's cost and my routine of changing it every three thousand miles. I personally use conventional Valvoline 5W-30 oil with an AC Delco filter.

I got my truck back today, and I could not be happier with the job that GM did. They replaced all the lifters and apparently GM Corp. wanted to have the parts in question in hand ASAP. They said they haven't seen many 4.8l with problems and want to see if it was a bad batch or just a fluke. The truck idles smooth as butter, I thought it idled fine before but you could barely feel it ideling. IE: if I had a plastic bag in the truck you could see the bag move slightly with the idle of the engine, now nothing moves and inside the cabin is super quiet. They also replaced my driver side window regulator and rear driver side power door lock actuator. Granted those were on my extended warranty but I walked out of there with a bill for $2700 and didn't have to pay a dime. They also washed and waxed the truck for me, it looks like it rolled out of the showroom floor and drives as if it is a brandnew truck. They told me to replace my oil after 500 miles and to drive it like I stole it.

it was probably driven like it was stolen before you got the truck , I Have the 1999 4.8 and it was used as a commercial truck for 5 years, owned it for the last 2 years and had service records along with it, engine Runs smooth with all of its orig parts. Throw in a tank of 89 octane and do what they said drive it like it was stolen, If they did good work rebuilding, it will show.

Also I try my hardest to change oil every 3000, went to 4100 miles 1 time, on a cold start the change oil light came on in random intervals, i guess contaminants passing by sensor, Change oil every 3k, and Hoping for 500,000 miles one day for now im at 190,000