Leaking front differential through third member attachment fasteners… (1 Viewer)

[Rocky_LC]

I recently tried to tighten up these loose fasteners (the nuts seemed to almost be unthreaded) at the bottom of my front differential.

Now they are weeping gear oil.

Are the nuts just screwed to studs that are threaded into the axle housing? Or are they some kind of special fastener?

If I wanted a little extra pain in the butt (because of two types of fasteners), could I just drain the diff, carefully drill and tap them to a larger size, and install three bolts, or Allen head cap screws there?

Thanks -

Rocky

 

[charliemeyer007]

There is a reason there is such a thing as torque sequence and an amount. Crushing things can make seals leak. +1 for make sure the mating surfaces are clean and flat. Some times a gasket compound is required besides an new gasket.

I like allen head bolts. Stainless steel can be a real plus, so is anti seize compound

 

[cruiseroutfit]

We stock them all @ CruiserOutfitters

For each diff you need:
8 x DIFF10103 (OEM Toyota Diff Stud L=37mm, S=12&25)
2 x DIFFA0025 (OEM Toyota Diff Stud 10x1.25mm, L=50, S=12&18)
10 x UJ94512 (OEM 10mm Drive Line/Diff/Spindle Lock Washer)
10 x UJ51000 (OEM Toyota 10mm Drive Line/Diff Stud Nut)

801-563-1277 or info@cruiseroutfitters.com to order

 

[pb4ugo]

The fasteners are studs. I think to correct the problem you'll need to pull the 3rd member. Maybe new studs or thread sealant and gasket. You'll have to pull the axles 1st. I'd replace the pinion seal too.

 

[Rocky_LC]

Thanks for the replies. This is a bigger project than I had anticipated, it seems to pretty much be a teardown of the whole front axle.

I may be letting them weep for a while.

Kurt - appreciate the information, I may get the parts on order for the next time I have a spare month (my projects tend to go pretty slowly!)

Thanks -

Rocky

 

[3_puppies]

is the pinion seal leaking also?
the entire diff looks all wet from the pinion down to the fasteners

 

[Blue77FJ40]

When installing diff, check out the below vid around 1:00 minute how they spread the figp on the gasket. I had leakage on my diff and had to redo it. I also had leakage from the studs. I had to remove the studs and add teflon tape for a good seal, cleaning both the studs and the tapped holes in the housing. You could also add blue lok-tite instead. Worked for me - no more leaks on the diff.

Footnote: no way could I lift my front diff (an FJ80 rear elocker) by hand anymore, I have to gizmodo a floor jack to hold the diff to do that now.

 

[Malleus]

Yeah, you don't have the tiny differential those pickups had in them.

 

[Steamer]

I would take note of what 3_puppies said and degrease the diff well to get a better look.

 

[Rocky_LC]

Thank you guys.

I am cleaning up the diff. I can’t really tell if it’s leaking from the pinion or if that’s just leaks from three studs on the bottom that is blowing back.

Appreciate the suggestions.

Rocky

 

[Paul_A]

Degrease everything. Those studs/nuts are the perfect place for oil to collect from other locations and then drip. I do not think you have to pull the diff to replace a stud, but I do think the studs go thru into the housing so oil will get by them if not thread sealed. If the gasket is weeping, the diff will have to come out. I recall a guy whose drain plug was wiped and he pulled a stud, changed it to a bolt, and drained it that way. (Not a recommendation but a quick fix.) All in all, though, not the end of times.

 

[Rocky_LC]

So I’m progressing forward, going to try and just seal up the diff studs.

Got all three of the studs on the lower side out, and am cleaning things up. Used the “two nut” trick. Studs look good.

Hoping the inner flange isn’t stripped, and things just got loose.

Once cleaned up, will apply sealant, reassemble, & torque & refill.

Can’t hurt, and lots easier than tearing the axle down!

Rocky

 

[Rocky_LC]

Hoping for a good outcome. Removed and reinstalled the studs, and cleaned everything up.

Seems like nothing is stripped because I was able to get 18 foot pounds of torque on the nuts.

Will soon see…

Rocky

 

[Green Bean]

Hoping for a good outcome. Removed and reinstalled the studs, and cleaned everything up.

Seems like nothing is stripped because I was able to get 18 foot pounds of torque on the nuts.

Will soon see…


View attachment 3428610

Rocky

@Rocky_LC I am about to tackle the same project; i.e., replacing the studs on the rear third member. I have ordered the new OEM studs. However, I'm not planning on removing the 3rd member. But rather replacing one stud at a time after draining the gear oil. Question: Were you able to have enough exposed stud to use the double nut method to install the studs without removing the 3rd member? Thanks.

 

[Rocky_LC]

Yes, You do have enough room when you remove the thick lock washer that is also there.

You don’t have to use all the threads on the second nut when you are installing the stud, just enough to get the stud seated.

You’ll also get more gear oil out of the bottom stud, even after you’ve drained the differential…

 

[jvincig01]

Hoping for a good outcome. Removed and reinstalled the studs, and cleaned everything up.

Seems like nothing is stripped because I was able to get 18 foot pounds of torque on the nuts.

Will soon see…

Rocky

Me checking to see if a single drop of oil suddenly appears under your diff...

 

[Rocky_LC]

Haven’t driven it yet, but filled it up with diff oil about 2 weeks ago, still dry!

Delayed getting my oil pan, and then it arrives without a plug, and of course they changed the size from the big ones to the new (tiny) 12 x 1.25 mm ones!!!

 

[Blue77FJ40]

This may help you on the oil pan...

ih8mud.com/tech/oilpan.php

 

[hobbes]

When installing diff, check out the below vid around 1:00 minute how they spread the figp on the gasket. I had leakage on my diff and had to redo it. I also had leakage from the studs. I had to remove the studs and add teflon tape for a good seal, cleaning both the studs and the tapped holes in the housing. You could also add blue lok-tite instead. Worked for me - no more leaks on the diff.

I just use blue RTV on both sides of the paper gasket, then let it set on the studs for 5 minutes. After that it’s normal assembly. Besides eliminating leaks from that gasket, it reduces gasket scraping to almost zero on disassembly since the RTV sets up on the paper, not the metal. No more paper or RTV scraping. I do that with any paper gasket now…