ayoung101

so i noticed i've got a bit of fluid dripping from my rear diff. from underneath, it looks like it is leaking at the front seal (where the driveshaft bolts to the diff) and is just dripping back to where the diff main body is. it looks fairly simple to dissasemble/reassemble to change the seal. anyone done this before? does it look easier than it really is (like almost everything else)? how much would a new seal (and gasket) cost?

also, stupid question: until (or if) i fix it, i can add fluid. is diff fluid the same as any other gear oil, same as my transfer case and manual tranny? thanks in advance!

kawasakimoto_7

haha i have the same exact problem right now... for gear fluid its 80w 90, at least thats what goes in mine, but it should be the same. i havent fixed it yet so i just continue to put fluid in until i get around to it, but the seal and gasket should be too expensive i hope.

Countryhick

theres a pinion seal around it but u dont need it.

When i put mine in all i did was put the new 3rd member in after blowing up my rear end.

Sealanted the hell out of it and put it on just be careful not to mess with ur sealant so you dont have leaks.

But you could just pull your rear 3rd clean all the gunk off and put new sealant on it and ur good to go. mine hasnt leaked and ive flexed it messed with it and ran it hard.

ayoung101

i didn't understand a 1 word you just said. i have ZERO experience and/or knowledge of the internal workings or diffs. i don't know what a pinion seal or a 3rd member is. i just look at it and see the 4 driveshaft bolts, and then 10-ish diff cover bolts and i'm assuming internally on the cover the seal is an easy replacement. anyone got pictures of what i'll see on the inside of the cover?

TOYOTA 1

http://www.4crawler.com/4x4/CheapTri...eal/index.html google is your friend

iamsuperbleeder

I guess I don't need the inner hubs seals on my spindle, or the rear main seal on my motor for that matter

TOYOTA 1

i think he is mistaking the pinion seal dust shield, for the actual pinion seal.

Justinlhc

Must be that season. Mine sprung a leak, too although mine is coming from the actual diff. Was fine before I got yanked out by my rear axle a few weekends ago. Oh well, it's the price you pay.....

[N8]

Indeed. My 94 started leaking a few weeks ago and I fixed it and now my 91 is leaking.

UKMyers

Most of the time those start leaking because the diff breather is plugged. When mine went a long time ago it sounded like I was letting air out of a tire when I took the fill plug out it had so much pressure built up inside the diff.

mikelusk1

you wouldnt need any gasket. just the seal. really easy job.

mikelusk1

and definitely make sure the diff breather is not plugged.

Justinlhc

Looks like I was wrong. It was infact the pinion seal. Strange thing is both AutoZone and Checker are calling my rear a 7.8" and not an 8". The seal took me about 20 minutes to change. Very easy. The old one was rock hard and took some convincing to get out.

Tubbyfatty

Yea i see that at a few places too.

mikelusk1

thats cause the physical measurment of the ring gear is 7.8 inches. bit it is known as an 8 inch

Jay351

x2!!!

I had a bad leak from the 3rd/housing seal. After taking apart the breather and using a screwdriver to jab the gooey sandy muddy mess that was plugging it, reinstalling the leak was gone

Took 15mins and $0

Justinlhc

I was hoping that's what my problem was, but I didn't get off that easy. A couple dollars and a couple minutes and it was fixed though. I like looking under it after it's been sitting for a while and not seeing wet spots on the ground.

ayoung101

ok, so i found the breather simply enough. how do i tell if it's clogged (and/or how do i unclog it)? just remove it and run water through it? when i screw it back in to the diff, do i have to use thread tape or anything to seal it?

i'm not holding my breath on this fixing my leak, cuz it's been a few years since i've been offroading, and the leak just started this spring. but i figured i might as well try it. but if it doesn't work, the other posts in this thread make changing the seal not look too bad.

874runnersr5

Take off the breather, get gasoline in a cup throw it in there for a hour take it out get a metal pick and see what comes out thru the bottom. Then blow some air thru it and see if the top part cover thing lifts up a bit and air will pass.
thatsmy best way of describing it haha.

Murakami

here's a good thread on changing the seal at the pinion:

https://www.yotatech.com/forums/f116...acment-152859/