Rear diff leak from fill plug & pinion seal

Just looking for what you all think is going on. Have toyota looking at it this week, but want to do my own research to try & understand what is going on.


Got my diff changed by some shop up the street, which I don't trust to go back & rehash things with, since then my rear differential is leaking badly. Not going to drive it until I figure out what's going on.

Leaking from the fill plug on the back of the diff, & leaking from the pinion seal I believe, ( where the diff and drivetrain meet ) wasnt leaking before, guy said it was low so they just drained & refilled. *supposedly*

Could it be that they overfilled the diff? or put it back together wrong?

 

Check the diff vent line or the little vent valve on the axle which ever you have. If it’s plugged and can’t vent the pressure will cause leaks. Those valves are known to get stuck.

 

The valve seems to move freely, the fill plug & opposite end of diff are leaking. Wish I could just tighten something down.

 

Try removing the breaker and see if you can blow air through it. Mine was plugged when I got the truck it started leaking out the seals a couple weeks later. Fill plug... maybe the washer was not put back on?

 

they probably overfilled it, didn't use a new crush washer on the plug, its possible the diff seal blew out if they overfilled it lots of pressure can build up inside of the diff. I would check the oil level first, basically they should take 3 quarts of oil, manual says 3.2qts I think

 

I swear I'm going to learn how to do all this work on my own. Thanks for tips fellas I appreciate it.

 

doing the diffs and transfer are easy, lots of how to's in 2nd gen

 

Has your overflow been spewing oil out? It looks like it may have been under pretty good pressure and sprayed some against the bed.

If so i bet they overfilled......however that's possible.

 

I had to get under there and wipe everything down like a dumbass. Where is the overflow ? Is that the cap like structure on the very bottom or are you just referring to it being overfilled? After I wiped it down you can see behind the valve where it started to go everywhere again. Only place I see where a leak would he is by the pinion seal & fill plug.

 

put a catch pan under the diff and take out the fill plug see if oil starts pouring out, if so they over filled it, take pictures of it so now the dude can fix the blown pinion seal he created.

 

If someone overfilled it I wouldn't trust them to fix a seal. May wind up with a ruined Pinion if not done right.


Many names ruined over hiring beginners to do fluid changes.

edit: another thing to think though is Did you drive through water after the rear end got warm?

 

Just let it drain til it stops then close it back up?

 

The refill, not the drain underneath.

Just to figure out if it's overfilled.

Going through water when the rear end is hot can blow out the seal also.

 

Nah I haven't drove through water at all, hasn't even rained much as of recent in WI

I read that somewhere as well this morning on a different thread.

 

I'm going to do that in a minute here.

 

Check fluid level from the fill plug, then do a diff breather relocate while you're down there.
https://www.tacomaworld.com/threads/differential-breather-mod-for-dummies-pics.15686/
https://www.yotashop.com/toyota-of-road-vehicle-differential-breather-extension-kit-1012/

 

I read threw the 1st few pages, that video doesn't load but I imagine this is to* get this away from any water that might go through. That was a dope as write up damn.

 

Yup. I put mine behind my tail light.

 

yes

 

Diff rebuilt/replaced? Or just a fluid drain/fill service? What does he mean by "it was low so we drained and filled"? It was low after the diff was rebuilt or before?

Im with @scottalot, you cant really over fill these things..