How do you change rear pinion seal in 2006 GMC 2500?

Here's a safe way to do it:

~First mark position of drive shaft mounting to yoke.

~Second, remove shaft.

~Third, take a sharp pointed punch and hammer and put a mark on pinion nut and end of shaft inline with each other.

~Fourth, remove nut "Important" count the amount of turns you make because that is your bearing pre-load.

~Fifth, Replace seal and clean yoke. Make sure you don't have a worn ridge where seal rides.

~Sixth, Put a light coat of rtv on inside spline and a light coat of grease where seal rides.

~Seventh, Replace yoke and replace nut turning the "EXACT" amount of turns to remove. Align marks being very careful you don't go past. Refill and replace shaft.

It's VERY IMPORTANT to line up marks with EXACT amount of turns to keep bearing preload correct. And you don't want to go past your mark then back off because there's a crush collar in most rears, if you over tighten it, it'll crush more and wont give proper preload.