Pinhole rear differential leak help with repair

[yotamaine]

I recently discover a leak in my rear differential on my 01 4runner it's probably 1/8 of an inch in diameter I was wondering the best way to take care of this, I've read that welding a plate over it works but don't have access to a welder, also read about a jb weld fix but not sure how well that would hold up.I thought about maybe using a sheet metal screw of sorts with a rubber washer to just plug it but not sure if that's a good idea, any ideas from you guys would surely be appreciated

 

[RedSled]

I recently discover a leak in my rear differential on my 01 4runner it's probably 1/8 of an inch in diameter I was wondering the best way to take care of this, I've read that welding a plate over it works but don't have access to a welder, also read about a jb weld fix but not sure how well that would hold up.I thought about maybe using a sheet metal screw of sorts with a rubber washer to just plug it but not sure if that's a good idea, any ideas from you guys would surely be appreciated

http://www.toyota-4runner.org/3rd-gen-t4rs/166480-rear-diff-leak.html

 

[Kurtis]

Just have someone weld it. I punched a hole in my diff years ago when the ring gear decided to take a bite of it. Just welded it up and it was fine. I'm sure a random exhaust shop would help you out.

 

[Cree]

.I thought about maybe using a sheet metal screw of sorts with a rubber washer to just plug it but not sure if that's a good idea, any ideas from you guys would surely be appreciated

That would work short term. Just have to get a screw that's slightly bigger than the hole. I'd trust that longer than I'd trust JB Weld. You'd still want to keep an eye on it. The nice thing is you know pretty quick if you're leaking fluid. Can't miss that smell.

 

[Nelsonmd]

Are you guys f-ing crazy? Don't put a GD screw into your diff cover. If it's so thin that it's leaking, then it won't hold a screw tightly in the long run.

No offense intended, but holy crap...

OP, this is very well documented, with more detail in other threads than the one Redsled linked. Do your research here and just make your decision.

That said, and again, please don't take offense at this, but...

...also read about a jb weld fix but not sure how well that would hold up.

so what have you read about it here? We have been pretty clear that JB weld lasts about 1-2 years. So you have a pretty clear decision in front of you, $5 for a 1-2 year patch, or more $ and time to weld on an aftermarket cover (or have you current one welded shut) and have it fixed permanently (or if you weld it shut, for who knows how long til you get another leak...)

If I had to do it all again today, I'd probably weld on an aftermarket cover instead of buying a whole new housing. That said, I now have a welder and could do it myself, which I couldn't do at the time.

You have all the info here on this forum already, you just have to make the decision for yourself.

 

[yotamaine]

Thank you for your replies I was just getting more recent information on this issue to see if has been approached in any other way than I have read about I've also thought about that flex seal stuff on tv the one that shows the boat with the screen door form the bottom sealed with it to prevent any leak but that's just a long shot I'm gonna go with the temporary j b weld fix for now until I can find a shop to weld on a new diff plate.

 

[Nelsonmd]

Thank you for your replies I was just getting more recent information on this issue to see if has been approached in any other way than I have read about I've also thought about that flex seal stuff on tv the one that shows the boat with the screen door form the bottom sealed with it to prevent any leak but that's just a long shot I'm gonna go with the temporary j b weld fix for now until I can find a shop to weld on a new diff plate.

Yeah, don't bother with the flex seal, it's not as good as it appears... JB weld is just about the strongest epoxy grip that you will get to bare steel. Just be careful with the application. Drain your diff and really clean the metal off with degreaser before you apply the JB weld and it should last a long time. Also, rough up the surface with some rough sand paper so you give the JB weld something rough to grip to.

Be sure that you clean off the entire cover and make sure you have found all the pinholes and plug them all, then be sure to paint to protect it moving forward. If you already have pinholes in one place, then you likely are very close in other little spots.

 

[Mark_BC]

Poked hole in differential housing

Oh man I was scraping the rust off the rear differential housing, unbelievable how much was coming off, and I accidentally punched the screw driver through and out came the fluid... about 2/3 of the way down the housing.

I see that JB weld is a good temporary fix, I'll go to Canadian Tire now to get some. Thinking that I'll drive the back end up on ramps on a hill so it aims downhill so the fluid sloshes away from the hole, then degrease, clean and apply. Hoping to use it this weekend.

I'd really like to avoid removing the fill plug. How much fluid needs to be in there to run it safely, in terms of how high up the differential should the fluid be, since I can estimate this based on where the hole is?

Also, do you think that a little bit of rusty material that went inside with the screw driver tip would cause wear on the gears or would it all stick to the magnets on the plugs, I assume the plugs have magnets?

Been lurking for a while, now I have a question to post so I'll be a more regular member now.

1997, Limited. V6.

 

[Mark_BC]

The fill and drain plugs came off pretty easily with the impact driver, the sealing surfaces are in good condition. It's a good time to change the fluid anyways. So it looks like a standard JB Weld repair job now. Thanks to this forum. Not a big loss, now I know how thin the metal there is and how to do a repair in the field if need be! I'll clean it up and then spray it with the anti-rust 3000 spray from Canadian tire.

BTW, I read above of people welding on a new aftermarket face plate for the diff, or welding plates overtop of the leaks. Can these operations be done when the gears are still in there or do you have to disassemble it? Dos the heat from welding cause a lot of gunk on the inside?

 

[UnderFire]

If your diff cover is that thin the only real fix is welding a new cover onto the back of it, you don't want to be going down the freeway and lose all your gear oil.

 

[Mark_BC]

Just ordered the Barnes 4WD cover plate, I'll see if a welder I work with can do it for me. As my 4X4 friend in California just said, it's a blessing in disguise, you don't want to find these problems in the middle of a Baja dirt road. He had a differential seize up on an International Scout years ago and had to hitch a ride back to Bay of LA on the old gravel road, way before it was paved.

It would be cool to take this rig to Baja this winter, got a list of things I need to do to it to fix it up. 4runners are sweet, just that pesky rust you gotta keep a handle on.

 

[silver4est]

My rear housing sorted leaking after I changed the fluid, I've debated on welding a plate over it, but swapping the pumpkin sounds better. Where are they sourced? I've only seen larger land cruiser ones

 

[mmendelscfi]

We went with the Barnes cover when ours leaked.

I suspect the entire axle will fall apart before the new cover fails.

It is quite robust.