pinion seal

[SicMonte]

simple question...how do you replace a pinion seal on a gm 10 bolt? any pointers?

[SicMonte]

ok....how about just general help on replacing a pinion seal...on a gm type rear.

[PRO TC]

1 remove drive shaft.2 take the big nut off in center of yoke.with impack. then you might have to hit the back of the yoke with a hammer to get it off. 3 pry seal out with screwdriver or chisel it out around the outer edge. pound new seal back in. now here is where it gets tricky put the yoke and nut back on and tighten with impack but dont over tighten. there is a spec you can look up
barry

[68nate]

Before removing pinion nut, use a center punch to make a mark on the nut and a mark on the end of the pinion shaft directly below the mark on the nut. After replacing the pinion seal, reassemble and line up the dots slowly. Do not overtighten the nut, it will overload the bearings.

[jpdeuce]

Retorque the pinion nut to 10-15 inch lbs if you have a torque meter. If not then there is a backyard kinda way. Take the slack out of the pinion yoke until it almost dissappears. Put a 1/2" drive ratchet on the nut in the 3 o'clock position. Let go of the ratchet and see if it drops quickly or if it drags slowly to 6 o'clock. If it doesn't then take another very small turn on the pinion nut and try the ratchet drop again. Once the ratchet starts to slowly drag then your in about the right spot.

Using a new pinion nut is reccomended. If you do not then once you have the bearing preload set, take a hammer and chisel to the nut and threads. Score the edge of the nut and the pinion threads so the nut doesn't back off.

[Josh]

GM 10 bolt uses a crush spacer to set pinion bearing pre-load. This is crushed to the right spec upon initial instalation. It takes over 300ft/lbs to crush this during set up. As long as nothing was changed in the inside of the diff, all you have to do is re-install the seal, yoke, and nut and tighten to 100ft/lbs with a little loctite on the threads and you are good to go. The crush spacer will be at spec as long as you do not crush it any more (300+ft/lbs of torque!).