Rear Diff Breather (Relocation) Problems?

Hey TW,

Wanted to get some feedback about potential side effects of the rear diff relocation "mod." Is it possible for the mod to have a negative effect on the seal and gasket? I was reading on another thread of how someone's rear diff was seeping from the sides and near the top from the seal. They claim that it could be a plugged up diff breather creating pressure as the housing heats up. The increase in pressure will blow oil past the seals and gaskets...is this possible?

I installed my rear diff breather using the same part numbers and instructional thread all over TW. I noticed while installing my rear suspension over the weekend that I had some MINOR seepage in various places surrounding the seal on the diff. No leaks - nothing out of the fill/drain plugs - just around the seal. Would it be possible that my diff relocation has caused this? Or is the 3rd gen just more susceptible to getting this kind of problem.

2017 TRD OR 4x4 DCLB w/ approx 31XXX miles.

***Pic from previous thread. NOT MY DIFF.***

 

I never noticed any seepage from prior to doing the mod - but I have also been wheeling more after the breather extension was added.

Its hard to pinpoint if it was either
1) the breather
2) 3rd gen being a 3rd gen
3) more off roading causing stress on the rear diff
4) ???

 

Thats not from the breather mod. Thats the weeping diff Toyota gave us

 

Oddly enough I knew you'd be the man who would help me out here @JaCado! I figured it was from the 3rd gen being a 3rd gen lol. If it makes a difference...I haven't noticed any changes in driving quality so that't a plus. Guess I caught it at the right time!

I removed the breather and put the OEM one back on just for safe measure before some BS was gonna happen.

 

If you take it in that's good you removed it. They will most likely just retorque the bolts. Keep an eye on it and if the spots get larger, get it back to the dealer.

 

I will ask them to check everything else too just for good measure. Thankfully one of my friends is an advisor there so the shit better get done lol

I am assuming they should also check fluid level?

 

if your lucky they will check the fluid.

 

Both when I swapped the diff lube and when I installed the breather mod, I found my diff had a vacuum. I feel the original breather was broken. That said, I had weeping around the seal even with the vacuum. Go figure. It might have been happening when the diff heated up and there was a positive pressure inside or just this weird seal problem.

I'm just happy that mine is a weep. No drips. I can live with that.

The breather that I got for the mod flows air nicely in both directions.

 

OEM wasn't broken, that's how it works, one way. So when the vehicle is cold the oil heats and expands and the breather let's the air out. Then when it cools again it's under vacuum.

 

Interesting. The part that I got (

$6 Toyota Breather Plug - 90930-03136

90930-03136) does not work that way.

 

OEM. Not the one u swapped it for. That's the whole reason for the swap, so it breathes both ways instead of one.

 

So it could be quite possible that I didn’t notice the initial seepage prior to installing my breather mod? It definitely could be possible...

 

Will typically start leaking at the axle seals before the diff.

 

I'm more curious if the vacuum from a stock breather helps mitigate any seepage on the rear diff, even if slightly.

 

It's been a few weeks. I'll take a good look at mine. I was under there looking that the clutch inspection plate. I didn't notice anything odd glancing back at the axle.

 

I was checking the axles and didn't notice any seepage. It could have been highly likely that I didn't notice any seepage from the diff prior to installing my rear shocks because I was never that close to it before without anything blocking my line of sight (spare tire, rear wheels, etc.)

Again..it's not on the bottom of the pumpkin but moreover on the sides and near the top. It has to be releasing gas but I'm curious to know if its just a bad seal/loose bolts or just a blockage of the new breather(?).

@tonered I have that same breather you have from toyota...what size fuel line did you go with?

 

More than the gasket, I think the source might be that most seepage that I have seen is at the seam on the axle housing. Even though the surface is machined for the 3rd member, I wonder if the weld is porous?

I went with the 1/4in I.D. rubber line from Lowes tubing / hose selection:
https://www.lowes.com/pd/EASTMAN-1-2-in-x-10-ft-Rubber-Fuel-Hose/1000180619

It was a squeeze to it get on the metal nipple, but doable by hand with a bit of grease on it. For the plastic nipple on the breather, I didn't want to apply that much pressure. I hit it with my heat gun for about 30sec and it slipped right on.

I have a little tool that makes neat little clamps out of SS safety wire.

This the only pic I have at the moment:



DON'T go with that location. I didn't have any VHB tape and a zip tie support on hand. If I did, I would have just stuck it to the bed behind the filler. I did this because I didn't want to drill into the fuel filler surround and didn't want to drill the cubbies since I have them sealed and full of stuff.

Someone posted a pic where they routed theirs behind the taillight. Great location, IMHO.

 

I wonder if it's machined prior to welding axel tubes on and it's warping from the heat. I routes mine behind taillight. Only downside I can think of, is it's not as simple to check on.

 

Shit I just looked at the pic of the axel haha. Maybe it's machined prior to the backside of the pumpkin cover being welded on.

 

Here was what mine looked like @roguegs
https://youtu.be/VxYn8kkp_ks