It appears, and smells, like my 5.9 is burning oil. What is the most likely issue, turbo or the piston rings? I'm thinking its a turbo, but I'd hate to put a new turbo on it and end up needing to put rings in it. The impeller does have a bit of side to side play and the engine fires off within one revolution, so I think the compression is good. Anybody think differently?

 

Probably be best if you could give us a little bit more information about your truck. Maybe start by completing you signature file so that we know what you are driving, any mods done to it and so on. Also would be good to know how many miles are on the beast and in general terms has it been rode real hard and put away wet more often than not. Just give us a bit more and the others will chime in.

Cheers!

Mike

 

You will see oil residue in the turbo and piping if it has bad seals. I would look at the valve stem seals next.

 

My bad, still new to the forum. I've got a 90 D250 with a 5 speed. It's stock minus the fuel pump is turned up a bit. It's got 230000 miles on it and a pretty easy life, was used to haul trailers but never hot rodded around. I bought it from a friend who took good care of it. Need anything else?

 

If the turbo is bad, there'll be quite a bit of motor oil in the air tube between the turbo and the intake manifold.

If the turbo completely chits the bit, you could get enough oil in the engine to cause a catastrophic runaway.

With good maintenance that's a million mile engine. Overheat or low lube, of course, voids that expectation.