Hello, Been finding good information on this forum for a while, and this is my first post.

I noticed my differential case was leaking some oil at the driveshaft yoke flange. I decided I would need to replace my diff. pinion seal, but after doing some more reading found out about the possibility that my breather was clogged, and sure enough it is corroded shut.

My question is; Can I just replace the breather and leave the diff. pinion seal alone, or is it likely compromised from having had oil pushed through it?

Note; I would like to just try to replace the breather and see if that fixes the problem, but I have to decide if I should replace the seal now (while I have access to tools), or wait and see if the breather change solves the problem (by which time I won't have access to the necessary tools, and would need a repair shop).

This is a 2001 Tacoma 2.4l RWD, 240,000 miles. Leaking is most noticeable after long highway drives.

 

One of those things you might get lucky then might not.

The hot oil builds pressure it needs to vent some place.

If you change your seal make sure to have the new nut and stake it.

can you live with the leak till you can fix it??

Clean the breather take it for a ride long enough to get things warm see what happens.

 

I would just do the breather myself and see what happens.

 

I second this ^ It's probably OK, jmo.

 

make breather lines, no more plugged breathers. I think I spent $14 for all the line and three filters to make mine. The fitting with the long nipple, , is the one I went with for the three.

 

Thanks for the input. Based on your comments, it doesn't sound like a bit of leaking from the pinion means the seal is necessarily shot... given that my breather has been non-functional. I will just change the breather for now and keep an eye on it. I have an 800 mile trip coming up, so I'll keep extra oil on hand, and give an update on whether I notice it leaking again.

I should note that it hadn't leaked very much in the first place, when I checked the level today, it was barely below the plug hole.

I am surprised there is no mention of the differential breather valve in the Haynes manual...I didn't know it existed until I checked around online about my leak.

 

The only time the pinion seal really gets piped from these types of issues is when a temperature change happens very very rapidly. That will cause damage to the seal every time, but when it's just the breather that's plugged normally the seals are fine.
Keep some extra gear oil on hand and keep an eye on it. Report back the results.

 

It seems the breather change solved the problem. I've put on about 2000 miles, including 2 900 mile days, and there is apparently no further leaking.

 

About 25,000 miles more and no leaking. Apparently the seal survived the clogged breather valve just fine.

 

Same story here, only it was the passenger side wheel bearing. Saw a leak, found the plugged breather, fixed the breather, cleaned up the oil, no more leakage.

Since then I put a remote breather on it.