Been reading for awhile and just joined. I recently bought a 2005 f350 DRW. Had a STC fitting fixed and they're putting in new injectors now. The truck puffs bluish white smoke on takeoff, thinking the seal is bad in the turbo. I've read where several people have rebuilt them. My question is how are they holding up? Is it worth doing or should I just buy another turbo? Mechanic says they're not worth rebuilding.