I have a 2008 1500 Suburban with 119K miles on it. 4 months ago and 800 miles ago I had the classic clicking of a lifter problem and had the top of the engine dismantled to have the lifter repaired and the camshaft exchanged. Now the Suburban gives off a big puff of white smoke on startup when it has been sitting overnight and the oil level has been slowly dropping. Does this sound like a broken piston ring or a valve seal. It doesn't smoke all the time. The service department states that it is the ring and thus isn't covered on their service warranty of 12months 12K miles. How does one prove it is one problem or the other.

 

how long did you drive it with the repair? could just be cleaning agents, or oil used when the reinstalled that is burning off. btw white smoke is antifreeze so perhaps they did not replace the gasket properly?

 

I would concur, I would be suspicious of a water leak into the cylinder... oil is usually a blue color of smoke... could be a gasket issue or as simple as a proper torquing of the head bolts...
How is the coolant level? does the oil look milky?

 

ASAP pay for a gas test in the coolant from another good shop to help find if a gasket is leaking. *BW*