ok im replacing my old blown t25 turbo on my 96 gsx with a used t25 turbo and basically with it connected to the o2housing still i was wondering what i should look for... in it being worthy to insall on my car

 

no shaft play, no cracks in it, no messed up/missing bolts.....

 

make sure its not seized up.

 

as with any used turbo i would suggest seals replacement. it will save you a lot of headache. look for no cracks on turbines minimal shaft play depending on if the turbo has "floating" rice bearings or not some garretts are required to have some shaft play for the turbo shaft to lubricate itself in those turbos some shaft play is good while no shaft play is bad usually indicates "coked" up bearings.