Had 2007 Duramax with LBZ in it come in with 185,000 miles & 8,600 hrs on it for oil temp issues. Truck is used to haul pipe. It was a no brainier that the oil was the problem after pulling the dip stick and seeing the next service do sticker. So took filter off and cut open seen no metal or foreign debris in the paper. Drained oil and man it stunk so bad, looked like I don"t know worse then black paint just nasty, but the oil came out,no clumps or goo. I was amazed at the condition of the oil. Customer says he only runs Valvoline 15w40 in bulk for everything, I have known the guy for 3 yrs now and that is what he uses even brings it to me if oil is needed for a repair.

I cant really knock Valvoline diesel oil after seeing this. I told customer even though nothing is in the filter it does not mean there is not any damage or problems going to come from it. He only wanted the oil & filter changed then back on the road the truck went. His driver told me 3,800 miles now and no issues. My thoughts are poor truck...you pay all this money for 4x4 LBZ Denali and you treat them like this. But its his money.

Im on a diesel truck forum for my current truck an ecodiesel. While I wouldn't do it and sure wouldn't recommend it there are people running 20k+ miles on rotealla 5w40 I believe and oil analysis says they can go further. Would have been interesting to see what the lab guys would say about that oil sample.

I change mine at 10k like Ram recommends.

Folks have their own reasons... but why would you risk an engine $5k and up (plus downtime) just to save $50-$100 on an oil change.

I guess some folks think it's a competition to see who can stretch it... kind of like seeing who can't can go the furthest on a tank of gas just to run out in the middle of nowhere.

Rant done.

I run amsoil 15w40 and change it every 10.000. 2005 GMC Duramax. I think I can go 15.000 but do it every 10.000