I have a leak through the rear diff pinion seal. I would like to pull the driveshaft, then pinion nut, then flange and then replace the seal. I changed the fluid about 30k miles ago, so I assume leave the pumpkin alone.

A couple questions:
What size is the pinion nut, 1-1/8"?
And it has been suggested to me that you are not to reuse the nut, has anyone reused it or is everybody replacing it? Anyone happen to have the part number easily available if you replaced it? It was suggested to figure the nut size when I pick a new one up, and that makes sense if going that route. I also understand that going this route I will have to measure how much thread is exposed, and set it back the same. I also read elsewhere that the nut will bottom out at a specific point? Anyone know torque spec for that nut? Or does that only apply going the route of opening the pumpkin and replacing the crush washer?

What's your experience?

 

PM Cheezit. He can tell you an easy way to do it.

 

The nut is an oem part, Ive reused them, ive replaced them. Getting the pinion nut tight enugh is challenge. To tight youll have an expensive faile, to loose is just as bad.
I do mine with an impact gun, and a holding bar.
Tighten till flange is sucked up, then adjust to correct preload drag.

 

What is the "correct preload drag"??? I have seen videos that say to count the number of exposed threads and adjust to that mark & also measure with a micrometer.

 

I am all about fixing what I can on my own, but I took my truck to my mechanic for this one when it was leaking on me. $250 out the door, I think is what I recall. A little spendy, but I was glad it was done right.