its not a load of rubbish but it certainly isn't needed as soon as the comp nut is off, and neither is it needed for a shaft and wheel change.
if your gonna be running 2.5 bar of boost through an 800hp engine then that is a different story im talking about stock motors running upto 1 bar of boost.

assumeing the wheel and shaft are in good condition I reuse them, or I have bought a new wheel and shaft assembly and fitted it with new seals/bearings and away you go.


ive seen some turbos that have worn so they were machined and custom oversize bearings fitted, the problem was the shaft ended up to small and eventually effectively twisted and jammed in the housings, I do all our turbos myself now and just scrap them when they've done there life.


when the wheels are worn from touching the case or foreign debrie or the shaft is worn out of tolerance for a new bearing to keep within spec then a new shaft/wheel is needed.
I havnt done a days college all self taught, its not rocket science a lot of it is common sense imo with a bit of research directly related to the job at hand.


its abit like the china knock off turbos, I have used and sold loads years ago, at 1 bar of boost they will run forever and a day but at 2 bar they don't last long.