Replacing Pinion seal

[hawk29]

I have a 2000 GMC sierra with 3.73's and the rear pinoin seal is leaking. What all is involved with replacing this seal? I have read that some people have changed the seal by removing yoke and nut and prying seal out and replacing. Is it really that simple? I had always thought to replace the pinion seal you would have to remove the diff, gears, and pinion shaft.

Thanks in advance.

[Colby 04]

drop the driveshaft at the rear end. remove the pinion nut holding the yoke. remove the yoke, pry the seal out. Gently tap new seal in. reverse for assembly. torque your pinion yoke to spec. top off gear oil in rear end. put kitty litter on oil stain in driveway.

good luck

[vhato]

You almost got it LCT, but you can't torque it to spec with the rear axle assembled. Here is what I would do.


1. Remove the drive shaft
2. While looking at the pinion yoke:
---a. Draw a line from the center of the pinion over the pinion nut with liquid paper
3. Remove Pinion Nut and Washer
4. Remove Pinion Yoke
5. Pry off Seal
6. Insert new seal
7. Slide on Yoke
8. Put on washer
9. Snug up pinion nut with LONG breaker bar or Strong Air Impact Gun.
---a. Make small moves until the liquid paper on the pinion nut lines up with the mark on the pinion.
10. Now tighten it a HAIR passed the mark. I mean a HAIR
11. Reinstall driveshaft.

All is well. Any professional gear guy will tell you that the entire rear end must be torn down and a new crush sleeve must be inserted. However, of these professionals that I actually know, I have witnessed all of them replacing real axle seals the exact way I wrote it. I have even witnessed the GM Dealer do it this way with warranty work. I have done it MANY times with no side effects. Just be careful not to tighten the nut too much. This is real easy to do.

[Colby 04]

One more thing I thought about....does the position of the driveshaft need to be marked on the yoke? That way its reassymbled in the same position it was originally?

[ipyro24]

I'm digging this one from the dead, but don't want to start a new thread. Do you use any special kind of sealer on the outside of the seal? I remember reading that you need permitex (sp) #2 on the splines or something... Can anyone shed any light on this?

[DG_97_Z71]

Last time I changed a pinion seal on my Chevelle, i wiped some permatex on the splines in the area where the seal would surround the pinion shaft to fill in the splines so it would not wick gear oil.

Little goes a long way.

[Roehl_909]

I'm digging this one from the dead, but don't want to start a new thread. Do you use any special kind of sealer on the outside of the seal? I remember reading that you need permitex (sp) #2 on the splines or something... Can anyone shed any light on this?

When I do pinion seals, I spread liquid teflon (GM spec) on the splines inside of the yoke, otherwise you get leaks through the splines. You don't need anything but the new seal and the teflon.

[ipyro24]

Actually, I think that is where mine is leaking from, the mettle shroud around the seal is totally dry, but around the pinion nut is wet... Is this common? The pinion has never been apart before.