Changing the pinion seal shouldn't be a problem, but getting the bearing
preload set correctly might be. You have to loosen the pinion nut and remove
the yoke. When you go back , it must be re-tightened correctly. You might be
able to mark it and probably get it close, but it should really adjusted so
that it takes so many inch/pounds of torque to turn it. I recall seeing
something about 16 inch/pounds, but you'd better check for sure. If you go
to tight and over tighten the crush washer, you'll have to start over with a
new one. Probably better to let someone else do it that has experience. I do
not believe this should be an expensive item to fix.
Ron