anyone know the torque specs for a 9.75 rear end pinion nut?

 

check out this official ford thread, http://fordracingparts.com/download/...and-pinion.pdf You are looking for 16-29 inch lbs of preload on the pinion with new bearings while tightening onto the crush collar. If you mess up you get a new crush collar. It mite take 3 or 4 to get the shim package right. Read constructions carefully. Usually Setting it up close to the exact same amount that came out make it very close. If you are using a different manufacturer you need to look at their set up package. Brand of Bearings etc. New ring and pinion of different ratio will set up slightly different. Back lash, gear wear pattern, side preload, pinion preload all are very fussy.