8.75 Rear Pinion Seal leaking

[cv70chall]

Upgraded to the 8.75 rear end a while back. When we had it on the lift, we decided to replace the pinion seal even though it wasn't leaking.
Ever since, I've had a slight leak from the pinion seal. I'm getting ready to remove it again and replace it, but I was told I might want to also replace the crush sleeve as well.

Any thoughts?

 

[burdar]

If there is a slight groove in the pinion where the old seal was riding, then you can get a leak there. You can buy a sleeve to install onto the pinion so the new seal has a flat sealing surface. Technically you are supposed to replace the crush sleeve when you take the pinion nut off. Some people like to mark the location of the nut on the pinion and just put it back in the same spot.

 

[cv70chall]

Thanks-
So replacing the crush sleeve this time when I replace the pinion seal again will solve the problem?

 

[moparleo]

Maybe, just be sure to lube the seal before installing.

 

[moper]

Check the yoke for grooving - use a sleeve-n-seal if it is. If it's not - you might look into rebuilding the chuck as the pinion bearings may be worn.
in regard to the crush sleeve - unless you have a rotating torque wrench (not the same as a standard torque wrench) I'd say just put it back on with a little blue locktite and forget about it. You should replace the crush sleeve - but you need to set the preload (or "crush") with that rotating torque wrench. If it goes back and is quiet it's fine.

 

[cv70chall]

Thanks. I know that the rear end itself has only 86k original miles on it and it's been quiet since we replace the seal the first time. Where can I get one of those "sleeve n seals" ? I
l will install that when we replace the pinion seal again just to be on the safe side- along with some permatex orange.

 

[moparleo]

It will be sold as a kit. The sleeve sildes over the yoke so it is a larger diameter than stock , this would make the seal fit tighter. Depending on the diameter of the sleeve, it may need a special diameter seal. If this is the case, then they would be sold as a matching set. It should be available from any major parts supplier. It may require special ordering but that is usually only a couple days.

 

[Chryco Psycho]

There are few issues here not even mentioned ,
1- I assume you have a 489 carrier , the 741 & 742 use shims Not crush sleeves .
2- the crush sleeve is a one time use only & is removed from the rear so you have to remove the ring gear & reset all of the lash & torque loads , be warned to crush a new sleeve requires 275lbs of torque . This is a good time to replace all the brgs too & check the condition of the sure grip which if you have a 489 should be the poorer cone design so you may want to look at a Eaton Tru Trac , it is a much better unit .
3- You can replace the crush sleeve with a spacer & shims this is a far better design , I always do this over using a crush sleeve
4- Check the condition of the gears also , you may want to replace them too , at least make sure the measure the backlash before disassembly to give you the best odds of resetting the gears so they do not whine

 

[moparleo]

Write this down. Good advice and there might be a test later......

 

[cv70chall]

Removed the pinion seal this past weekend- found some chew marks that resembled vice marks on the inner shaft portion of the yoke which was weird. Gently sanded down all the rough spots with fine paper until smooth. Applied some permatex red on the inside under-lip of the new pinion seal and reinstalled it. We used a torque wrench to work the housing back on and it seems to be behaving. Best part of all- no leaks...
My long-term plans are to replace the 2:73 open setup with a 3:23 POSI. At that point, everything will be replaced.
Thanks for the assistance!