Rear diff (3rd) seal leak

[TN_LandCruiser]

A couple weeks a go I noticed a small leak from the front of the rear differential just behind the coupler between the DS and the diff. I dont know exactly what to call this... This leak has become much more prevalent in the last two weeks and it now leaving puddles of stinky gear lube everywhere I park.

Does anyone have experience with this seal leaking and if so, what is the easiest way to fix it??? I can get pics if necessary.

Thanks!!!

[Beowulf]

That sounds like your pinion seal. I have not done that repair so not much advice on that. The "coupler" is called a Universal Joint; aka U-Joint or "uni" in OZ.

-B-

[TN_LandCruiser]

Yes, thats it...THANK YOU. Its the rear pinion seal...ok, now that thats identified...who can tell me how to fix it? That gear lube stank is eating my garage walls!

[Shipwreck]

The first thing I would do is remove the drive shaft and check the torque specs of the pinion nut. Pinion seal leaks can be indicative of a loose pinion nut which then allows movement of the upper bearing and excess wear and leakage at the seal. IIRC the torque should be in the neighborhood of 160 ft/lbs and the nut should be staked properly.
If all looks good, then remove the nut and pull the pinion flange. Check for a groove where the seal rides. If there is a significant groove, the pinion flange will either need to be replaced, or a speedi sleeve placed over the groove. You can now pull the pinion seal and tap in a new one. Check the washer underneath the seal for grooves and wear. This washer can spin around the upper bearing if the pinion nut was loose. Once the new seal is in place, put the pinion flange back on and tighten and stake a new nut.
There... You're done.

[TN_LandCruiser]

Originally Posted by Shipwreck

The first thing I would do is remove the drive shaft and check the torque specs of the pinion nut. Pinion seal leaks can be indicative of a loose pinion nut which then allows movement of the upper bearing and excess wear and leakage at the seal. IIRC the torque should be in the neighborhood of 160 ft/lbs and the nut should be staked properly.
If all looks good, then remove the nut and pull the pinion flange. Check for a groove where the seal rides. If there is a significant groove, the pinion flange will either need to be replaced, or a speedi sleeve placed over the groove. You can now pull the pinion seal and tap in a new one. Check the washer underneath the seal for grooves and wear. This washer can spin around the upper bearing if the pinion nut was loose. Once the new seal is in place, put the pinion flange back on and tighten and stake a new nut.
There... You're done.

Well that just sounds to easy to even be called a repair...Im guessing its a tad more labor intensive than you make it sound...LOL.

[MarcoPolo]

Originally Posted by TN_LandCruiser

Well that just sounds to easy to even be called a repair...Im guessing its a tad more labor intensive than you make it sound...LOL.

How did that work out for ya? Got similiar work to do on my 40.

My pinion has a slight bit of movement however... maybe take care of that come fall/winter.


Marco

[TN_LandCruiser]

Havent gotten around to fixing it...but need to. Its pouring out. Entire underside of the truck is covering in nasty gear lube. Found a local axle shop that will hook me up for $50 if I supply the parts and remove the DS. Looks like CDan can get the parts for me for around $30, but the shipping is more than he could save me, so Im going to prolly call my local Yota shop.

[Tools R Us]

There is no torque spec on the pinion nut. It's an adjustment, the nut is tightened until the preload/rolling drag on the pinion bearings is correct. The tension is maintained by a crush sleeve that is between the bearings. That sleeve is single use, so the only way to correctly do it is to take it apart, replace the sleeve and set it up properly.