1994Vmax

iTrader: (4)

Me too. It always ran fine when I drove it and did for this other guy too until one day. Not a steady degradation of any kind which leads to a failure. The oil pressure is puzzling though but a lifter or wiped cam lobe I am sure would do that. You don't see that many non AFM ones have catastrophic failure so I really would like to see what happened to this one. I promise I will update once we know actually what happened. Too bad it's a warranty deal as I wouldn't mind getting the engine from the truck to build a stroker from.

1FastBrick

iTrader: (17)

Would Be nice depending on the damage and the cause of Failure assuming it's doomed and not repairable under warranty.

I am wondering if there is a design flaw in the oiling system thats adding to the failures.

1994Vmax

iTrader: (4)

The only update thus far is the engine is being torn down at the dealer and a lifter failure is one of it's problems. The extent of the damage to the engine in the truck is not known yet however for sure. Did one just simply collapse or did one manage to turn and wipe the cam, that I don't know yet!

1FastBrick

iTrader: (17)

Nice....

ITSAGAS

Uh, wouldn't this motor be a 6.0 not a 6.2?

1994Vmax

iTrader: (4)

LY6 = 6.0 Liter, Iron Block, L92 Heads, No AFM.

TXSZ66AVLANCHE

iTrader: (7)

Last week I tore down a LY6 with 182K for persistent random misfire and ticking, a couple of the intake valves had enough carbon build up to keep the valves from fully closing.

1994Vmax

iTrader: (4)

Not surprising as in factory trim these engines run pig rich all the time. I thought the old LQ4's were bad for black sooty build-up above or aft of the tailpipe but these 07 ups took that to a whole new level. Then the mileage they get reflects that as well. A decent tune would probably make a world of difference there.

Either way I might call the trucks driver sometime this afternoon and see if he has heard anything new about the truck from the dealership. I want to know why a lifter imploded, lol.

01silvy

My instructor when i was going to school in GM's ASEP program told me they run them rich to help with emissions somehow.. Im not sure why they do that though.. I'm intrested to see what the outcome is with the truck though.

MyLS1Hauls

iTrader: (2)

Running it a bit rich at WOT helps keep combustion chamber temps down, which reduces NOx emissions, but it also helps keep the piston and exhaust valves cooler. You have to remember that these engines/trucks are designed to pull a full weight trailer up the side of a mountain in 100* heat, without failure.

As for the carboned up valves...I'd say that's from oil leaking past the valve seals, not because of a rich A/F mix.