I've got a buddy that has an '05 ext. cab with the 5.3. He has (i think) 215/220 cam along with springs and retainers, long tubes, intake, gears, and coverter, as well as a mail order tune.
he never runs it hard, no doughnuts, burnouts, and only the occasional race on the street here and there. i bet he only has a few thousand miles on his cam. he went to change plugs, and i think the number 2 plug, not sure, it's the front plug on the passenger side was burnt bad. he loses over a quart and a half of oil within a few hundred miles. we think its a ring problem. we just dont think that he has the mods to hurt this motor like it is. He says that the tune didnt take into consideration the 2degrees in his cam and that could be the problem. i'll post up some pics later. but what do ya'll guys think?
Tune problem to cause this, or just bad luck?
thanks,
-Kyle

 

Well that really doesn't sound like a tune problem if its only one cylinder. BTW the passenger side front is the #1 cylinder. i don't think the 2 degrees advance would hurt it unless the mail order tune desensitized the knock sensors to a point where they couldn't pull timing if it was detonating. If he's burning that much oil it would make sense it was a ring problem. i would check the compression in all the cylinders for sure. that should give you a better idea if it's the rings.

 

It's #2 plug on passenger side.
Was there any oil on the spark plug?
I'd bet its a ring but wouldn't rule out a damaged valve seal.

 

we were gonna take it and get a leak down test done.
and yes, i believe there was oil on the plug.
btw we're not really concerned with how bad the motor's hurt, he's buying a lq9. Just wondering if it's the fault of the tune for the sake of him going with another tuner with the next motor he gets. But we have no way of knowing if it was the tune, so that's why i'm not saying the name of the tuner. No reason in bashing someone for a potentially wrongful accusation.

 

It's possible it could be the tune. But hard to say. That's a risk you run with ANY mail order tune tho. The tune you get is based on experience with the vehicles. Everyone's vehicle is different, so If his was doing something that the tuner didn't know about then the tuner couldn't compensate. There's not often an issue but the only way to get the tune really accurate is when the tuner has access to the truck and can do some logging.