Rear diff pinion seal leaking.

It's leaking near where the drive shaft connects to the differential housing.

Is this a "take it the diff guy" job? Or can my mechanic do it?

Is it recommended to replace the crushwasher with a spacer, that's one thing that was done in a simular thread...
Is the oem pinion seal my best bet or are there better manufacturers?

TIA.

 

bump

 

Mine seeps just a smidge after doing gears. It does not drip fluid but instead there is a thin film around the pinion seal. Interestingly, it only does it on long highway drives. Keeping an eye on it.

 

TTT

 

Did you check the runout on the flange yet? Theres a little tool (cant remember it for the life of me) that you position and it indicates run-out on the face of the flange, and outer edge.

If you have excessive runout, it might be a bearing going that is causing hte seal to bite the dust.

 

undo the 4 bolts to take the drive shaft off... mark the big bolt with a permanent marker... get a breaker bar and make sure to count the number of turns it takes to get off... pull the unit out, might need a rubber hammer...pull the deal out with a seal puller or screw driver ...replace with new seal .... tighten bolt the EXACT same amount... bolt everything back up and degrease it...

 

Is that big nut staked?

 

yes it is.. shouldnt take too long to do, maybe an hour or so. i just recently replaced that seal in my driveway and it was super easy. what took the most time was getting that damn flange to come off the diff! i had to hammer it off millimeter by millimeter and finally after i could barely lift my arms i got it to pop off.

 

Anti-seize. I coat my flange mating surfaces with it. I take my driveshaft off often enough where it makes sense. I don't get the horrid smooth surface, rusted together, stiction anymore.

 

Sweet, thanks for the replies guys.

 

Any other feedback before I do this job next week?

 

Not to be a buzkill, but if you do it that way, you will never get it tightened correctly. The crush sleeve is a one-time use item. Once you release the load on it, it never snaps back exactly when you re-tighten it. That being said, if you want to try and reuse the crush, then when you tighten it back up, turn it an additional 5-10 degrees past where it was in the first place. Preload on the pinion bearing needs to be accurate to reduce the risk of damage.

Now I am not saying that your method will cause a failure or what not. What I am saying is that your method will not tighten it back down to the same tightness is was before it was loosened.

 

Thanks BamaToy,

I've found very little info on here and ttora. But what I've found as far as this job is concerned is to either: tighten by the way of original bolt turns to remove, then add 1/32 to 1/16 clockwise turn; (or) tighten to original bolt turns, then using a small caliber torque wrench tighten between 6 to 7 ft lbs. Both ways recommend to use red loctite and re-stake the pinion nut.

 

basically what I did for mine to replace the seal. mark it, replace the seal put it all back together and give it a little extra snugness on the turn and re stake it.


also check and clean your breather plug. i have been told if that is clogged it can force fluid out of the seals.

 

Good point in bold.

 

Thanks. Breather seems to be functional. But I'll be doing the b.r.m when I get the parts this week.

I'm fairly sure the leak was aggravated by my bamf diff skid, caused by maybe air current at hwy speed? Lost almost a qt over 600 miles vs an ounce or two over the same distance with it removed....

When I pulled the flange it appeared to be leaking from behind the flange, between the pinion seal lip and the drive pinion.

 

Wow, I suspected this with my BAMF skid also. I thought I might be crazy to think it, but I had the pinion guard snugged down pretty good. It's almost as if the clamp was so tight it was distorting the seal just a bit.

I backed off the tightness of the clamp and I think has reduced or stopped the seeping fluid altogether.

 

Yes, me too originally. But if over tightening it is the issue, then I think the damage is done... I've loosened the skid, removed it, reinstalled it all while traveling from the bay area to seattle, to Monterey, back up to the North coast, back to death valley... Only to have diff oil spew with it on.

But I think the pinion guard of the diff diaper is what's the problem, by having hwy speed air flow push in on the seal at a strange angle causing it to leak. :shrug:

Although when I bought the truck 5 months ago I did notice a smedge of buildup on the housing around the pinion seal. So it may have already been blown out. When I replace the seal, I'll keep the front diaper bolts hand tight and see how it goes from there.

 

Interesting. Mine did not seep until I did the regear with the new seal. I was running the diff skid before the regear without any leaking.

 

I bought my truck regeared. My old 1st gen (stock gears) didn't leak with the same diaper that the new one has. Weird.