i have my 97 f350 powerstroke and i think the turbo bushings are going bad.when the engine is cold,at about 1900 rpm there is a slight screeching sound,i am sure its the turbo.whats weird is after the engine gets good and warm,the noise goes away,and doesnt do it at all.turbo always seems to spool up no problem,even when this screeching happens.i am thinking of getting a kit from riff raff,and doing it myself.im pretty sure i am going to answer my own question on this,but does anyone have an experience where you cant rebuild the turbo?any questions or advice are greatly appreciated !!