Topic: Rear Pumpkin Leak (Driveshaft Side)

[Mozman68]

Okay...searched, but nothing came up on this...and I'm pretty sure it's an easy fix.  But if I haven't had to pull it apart before than I have no idea what I'm doing.

Noticed a small leak under my rear diff a few weeks ago.  Looks as though the seal between my rear drive shaft and diff is letting a little fluid out.  I'm not too concerned about it.  Checked the fluid level and it simply isn't losing enough to cause any issues....but I guess it could considering my new commute of 100+ miles a day three days a week.

I really just want to fix it so I don't have the small drops of diff fluid on my garage floor.  Any advice??  Have never pulled the drive shaft before and don't want to if it's going to be more trouble than it's worth.

Thanks!

[neale_rs]

With air tools, it would be a quick job.  Without, it may be tough.  I'm about to do this on a D35 I'm parting out. Aren't you putting in new axles soon? Might be better to just live with it for a while.

[Mozman68]

With air tools, it would be a quick job.  Without, it may be tough.  I'm about to do this on a D35 I'm parting out. Aren't you putting in new axles soon? Might be better to just live with it for a while.

Yep....a few more months until the new axles...hopefully over Xmas.  Was just wondering if there was a simple gasket or rubber seal that could be replaced by removing the rear drive shaft.

No big deal I guess..THANKS!

[Jeffy]

It's probably the pinion seal that's leaking.  If you haven't overfilled the diff then it's probably torn or worn out enough to leak a bit.  The only PITA part is that to reset you pinion preload you need an lbs-inch recording torque wrench.  Some people do do it without checking the preload though.   The only problem with the seal leaking is that if it's too abd dirt and water can get into the housing and cause the pinion bearing to go bad.  The seals are pretty inexpensive though.  Around $5 if I remember right.  If you're not wheeling it then I wouldn't worry too much about it since you have new axles.

[Bounty Hunter]

A slightly leaking pinion seal won't drip on the floor, it'll only keep the bottom of the diff wet with oil.  I'd replace it asap before it gets drastically worse.  It isn't too hard if you follow the instructions here

Happy wrenching

[Mozman68]

Well...I think what is happening is that it IS slightly leaking and during long driving the spinning shaft draws out some fluid and it slowly works it way down to the lowest point...bottom of the diff cover.  Stil, like I said, it's not like I'm losing a ton of fluid.  Been leaking for a month and I may have only lost about 20 drops...looks a lot worst when it spreads out on a nice clean garage floor.

[jagular7]

Also, remember oil spreads thin. So what looks like a lot of leakage is not necessarily a large leak. Just keep an eye on the puddle that is left when parked.

[Mozman68]

Also, remember oil spreads thin. So what looks like a lot of leakage is not necessarily a large leak. Just keep an eye on the puddle that is left when parked.

Yep....a single drop can make a 1 to 2 inch spot because of how thin gear oil is. 

Again, I'll change the diff oil as usual next month and keep an eye on what's coming out...it has it's good days and bad days. 

[Liljeepz]

I just replaced mine, it was $26 at the dealership, $23 at auto zone and other places, but they all had to order it, dealership had it in stock. Its a fairly easy change, 15-20 mins max... hardest part for me was getting the old one out.

[Jeffy]

I just replaced mine, it was $26 at the dealership, $23 at auto zone and other places, but they all had to order it, dealership had it in stock. Its a fairly easy change, 15-20 mins max... hardest part for me was getting the old one out.

$26 for the seal?   

[jcsanders79]

Yeah I paid around $6 for mine.