Rear Diff. Leak Question.
 

1992 4Runner

I lost almost 2 quarts of lube in about a week and it drips all the time. I thought it may be the breether preassure thing, so I cleaned it off good and I didn't hear any hissing last time I refilled it.

There is a lot of splattering on the underside so I figure it must be on the drive shaft. It looked like it was coming from between the round disc at the end of the driveshaft and the very front of the diff. Is this the "pinion" seel or is it something else?

Lastly, can I fix it myself (I'm not very good with axles) and what are the costs involved if I have a shop do it? Thank you.

Lamm

i had a leak there once. it was right after i had a chipped rear diff pinion gear fixed, in fact my truck was still at the shop. turns out it was the pinion seal. it seemed as simple as pulling the driveshaft and placing in the seal.

Cool, anyone else run ito this?

Lamm

I had a leak at the input shaft of the transfer case. To give you an idea, it took me about an hour to replace the $10 seal. The dealer wanted $100.

Yeah I know, it's not the rear diff, but I am pretty sure the R&R is similar in nature.

mine just started leaking too... looks like we both will be digging into it to replace the seal.....

Sounds like the pinion seal to me too. I had the same symptoms-lube sprayed underneath the truck around the front of the differential.

I've got the leak too. Seems to be coming from the seal of the pumpkin itself. My buddy thought I might have to take the axles out to replace the gasket, but I don't think so. Anyone know?

in order to remove the 3rd member you much remove the axles

Not necessarily. You can just pull them out a few inches and support the wheels so the axle is level with the housing.

Pinion seal is straightforward to replace. Mark with chalk the rear u-joint and driveline so you can put them back like you found them. Undo the rear u-joint bolts and detach the driveshaft. Now heres where it gets sticky....the pinion yolk nut is pretty darned tight, so either an impact wrench or alot of ooommmph with a breaker bar is needed. Problem with a breaker bar is that you will be rolling the truck back and forth by torquing on that pinion nut. Having somebody stand on the brakes helps quite a bit.

Remove pinion nut, slide yolk off, and now you have access to the pinion seal. Pry the old one out with screwdriver, being CAREFUL NOT TO SCRATCH the pinion itself. Pop in a new seal, retorque the yolk, line the driveline back up...you're done.

3 beers time, tops. With an impact.

i *think* i fixed my leak with out takeing anything apart.... i crawled under it to take a look and 1/2 the nuts were loose. tightened them up and its not dripping anymore. i will clean it up really good tongiht and see if it gets moist any more.