The fact that it smokes indicates it's getting the fuel. I would consider doing a "motor flush" it cleans all the oil systems. I am making a guess that the truck has been shut down too many times with the turbo hot, and the heat has burned up enough oil in the bearing to have the "coke" binding up the bearing. A motor flush will clean all the deposits out of the pressurized oil system, and perhaps make your turbo function. If not, I would guess the bearing is smoked from shutting down with the turbo spooled, causing wear from spinning on a dry bearing.
A simple way to see if the turbo is sticking, is to pull the air cleaner boot to the turbo inlet off, and see if it spins freely when cold.
If you do a motor flush make SURE to follow the instructions. The stuff thins the oil, and can scatter your bottom end if you load the engine up with it in the oil. Fantastic product, though. I have seen it bring compression up substantially by cleaning out carbon deposits from the ring grooves, and oil pressure come up notably. Good stuff to run through before an engine overhaul, too. Saves a LOT of parts cleaning effort.
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01 24v 100hp tips, 4"ss BDbrake &steering brace PSCpump 1.5"dom steering tapped box 1.5"ram manual CAD switch dual carters 3.55's LSD, big shaft nv5600/241HD 6 35's inners pulled in (no spacer) Ugly black and thrashed!