Yeah I would think so too. When I first got the truck this January it ran perfect for about 3 months then I ran into the blown plenum symptoms...So I suspect it had been leaking for about 8 months.

 

Does it run right yet?

 

It's hard to tell with the intake and cooling system still out of the truck lol.
I'm finishing it up this week.

 

Considering that the oil that is there is the oil that has not been sucked back into the cylinders the oil leak is worse than you think. More oil than that has gone back throughthe system. Remember this oil is not a fluid leak it is oil mist from the crankcase. And that is enough oil to need to check cat again and possibly replace upstream O2 sensor.

It will run a lot better with that fixed. Are you doing timing set and water pump at the same time?

 

Got done with the truck tonight; plenum, new radiator, water pump, oil change, and I quieted it down with a super 44 muffler. Also needed a new injector as one of 'em was cracked.

The truck definitely has a lot more power on the road. It seems to idle decently but the needle on the tach still bounces up/down by a few rpms, which I assume is a vacuum leak somewhere...I'll save that for another day. I still need to check the plugs to see if they're good, they've been in 6-8 months with the blown plenum (but there's no misfiring, even in 5th gear/low rpms.) And I'll throw in some seafoam tomorrow, see if it helps out the idle.

 

Sounds like a cracked head... probably between the valves. Have you done a compression check?

 

So could you tell where the gasket was leaking? it looked to be in tact to me by the pic?...
Are you sure it wasnt blowby from a failing pvc valve? I would replace that as well if you havent..I've heard a dealer one is best for correct flow...