Duramax lb7 white smoke and shaking
 

Yesterday I got home and parked my truck in the driveway but before I shut the engine down she was shaking bad and I noticed a large amount of white smoke blasting through the blow-by. I popped the hood and the whole engine was shaking left and right. There is also white smoke blowing out of the exhaust. The smoke is hard to see out of the exhaust but not the blow by. What is the problem?

spent ring maybe?

What exactly is the "spent ring"?

a shot piston ring

That would lead to burning oil right? Because the smoke is white. I always thought if it was oil it would be blue.

no not 100%. if you have excessive smoke coming out of the oil fill cap then its probably a shot ring

What about the dipstick tube? Smoke comes out of there!

yes than probably a ring.

The white smoke is unburned diesel. It is making it past the piston into the crank case and comming out any holes available. There is a chance, while rare on the LB7, that the piston is cracked. If the injector got stuck in the open position it may have also burned a hole in the piston.

The duramax is not known to get bad rings much, but it has had it's share of injector issues and a few cases of holes getting burned through the pistons from it.

Also, I just experienced a turbo that was pressurizing the crank case ... It was a bear to check but it was real obvious....

Had to make a down tube from oil return, put into small pan with oil in it ... started and sure enough, turbo was makin bubbles, So with tha said ...

It could be multiple issues all leading into one ..... I would start with Compression test and leak down and go from there, no need to go pulling it all apart for an injector if that is the real issue ..