This is a real tuff one. Actually the job can not be properly done as intended although we all do it, CAREFULLY!
The crush washer is NOT what you see under the nut. The crush washer is located on the pinion between the bearings. When originally installed the whole thing tightens up and the bearings are not tight as the inside races are spaced too far apart by the CRUSH washer. SO... one tightens the poop out of it till the crush washer crushes. This is done slowly with the bearing endplay continually checked as the inner races get close together.
The proper bearing clearance is not like the clearance of a wheel bearing. Thse bearing are designed to run under preload. SO... one tightens the pinion nut using whatever force till the bearings are so tight that it takes the smaller torque to turn JUST the pinion and two bearings.
This can not be done with the ring carrier installed and is done in original set-up.
As it turns out the bigger torque is probably less than what it takes to crush the crush washer any more. YOU DO NOT WANT TO CRUSH THE CRUSH WASHER ANY MORE. SOO... make a mark next to the original nut position (an accurate mark) and pull it to the larger torque being sure not to tighten the nut past the original spot.
Bosch Master, ASE Master, L1
33 years MB technician