Rear Pinion Seal Woes

Nic · Post by **Nic** » Tue Sep 28, 2021 8:13 am

All,

I have recently replaced a leaking rear pinion seal with a new one from John at Midwest I included the paper washer and felt seal in the re-build.
I parked it up after a quick run and this evening noticed the ominous drip of oil cascading over the UJ of the prop shaft. I tightened the nut to about 40/Ibs torque

Could someone please confirm that the nut should be torqued down to 220ft/Ilbs and the reason why this should be so high? Am I correct in that its something to do with the pre-load?

Thank You

Nic

Post by **wesk** » Tue Sep 28, 2021 10:32 am

Your assumptions are correct and your figures are correct.

These differential input shaft leaks are usually caused by the age old wear grooves the seals rubbing against all the dirt leave on the shaft. The two possible solutions for this seal groove problem are the added shaft sleeves that give a new straight rubbing surface for the new seals or a new input shaft. Also the metal shell of the new seals must be RTV'd to the diff housing. Note also that drive shaft splines are also RTV's during assembly.

Nic · Post by **Nic** » Tue Sep 28, 2021 10:52 am

Thank You for the guidance Wes.

Regards

Nic

Post by **jake138** » Sun Oct 03, 2021 7:47 am

Redi Sleeve 99156 is the part number you need, you can search around for local suppliers if you'd like, Amazon is the cheapest I've seen:

https://www.amazon.com/National-Seal-99 ... B000C5JNDS

The front pinion and rear pinion yokes, as well as the both front and rear outputs on the transfer case, all use the same sleeve. They've very easy to install, instructions are included, and they are much cheaper than replacing the entire yoke with some offshore junk.