Where is my Differential Leaking?

[Gebo]

As I have been installing a rather expensive Toyota OEM muffler and tailpipe on my 2002 4Runner I noticed a wet rear differential.
My drain plugs are tight. Any ideas as to why the diff is wet with fluid???

Somebody told me, in my vernacular, to check the "blow hole". DIrt daubers are bad for clogging it up????

I am gonna drain it this afternoon and see how much fluid comes out.

 

[JoelB]

Clean it with degreaser and a stiff brush, maybe some brake cleaner. Only way to really identify where it's coming from.

 

[jeepman3071]

Clean it with degreaser and a stiff brush, maybe some brake cleaner. Only way to really identify where it's coming from.

+1

On those Toyotas I've seen the rear "cover" of the differential rust through enough for the fluid to start seeping out. A flawed design in my opinion because you cannot easily replace just the cover.

 

[swampdodo]

As I have been installing a rather expensive Toyota OEM muffler and tailpipe on my 2002 4Runner I noticed a wet rear differential.
My drain plugs are tight. Any ideas as to why the diff is wet with fluid???

Somebody told me, in my vernacular, to check the "blow hole". DIrt daubers are bad for clogging it up????

I am gonna drain it this afternoon and see how much fluid comes out.

I believe the 'blow hole' is the vent tube or vent valve...



It allows the diff to 'breath' without debris getting into it...sort like a limiting check valve in a way. However, it is not perfect as crossing deep water can get water into the diff. This is why you should change/check your diff fluid after deep water crossings. Jeep and Toyota (and others) who frequent off road will 'extend' these with a hose to higher level to prevent water intrusion into the diff.

 

[swampdodo]

Are you sure that's diff fluid and not brake fluid...you might want to check your hard lines attached to the rear axle housing...

 

[JohnnyG]

With all that rust and pitting underneath, it's probably seeping out just about everywhere on that left side.

 

[Gebo]

Shoot, I was hoping I wouldn't have to do any cleaning but you guys are correct. Fiddle sticks!

 

[Gebo]

Are you sure that's diff fluid and not brake fluid...you might want to check your hard lines attached to the rear axle housing...

Well now you have thrown a wrench in things. LOL

 

[BigCahuna]

The oil might be leaking from the seal where the driveshaft is, and just blowing back on the pumpkin. Look the whole rear end over.,,

 

[Trav]

If it is rotted through you can fix it with a weld in piece. Not easy so unless you have a good welder and are skilled it may be better have someone do it for you, the diff is better removed to do this job and the old piece cut out nice and clean and properly welded. This is just one, there are many.
You can add a little dye to the fluid and use a black light to help find the exact location of the leak.

https://www.amazon.com/APDTY-Differential-42110-35680-42110-35681-42110-35700/dp/B07HFFPNQL

 

[2EHA]

A flawed design in my opinion because you cannot easily replace just the cover.

that’s just how every banjo axle is. complete carriers are much faster to swap and set up than a salisbury type

 

[ARCOgraphite]

As I have been installing a rather expensive Toyota OEM muffler and tailpipe on my 2002 4Runner I noticed a wet rear differential.
My drain plugs are tight. Any ideas as to why the diff is wet with fluid???

Somebody told me, in my vernacular, to check the "blow hole". DIrt daubers are bad for clogging it up????

I am gonna drain it this afternoon and see how much fluid comes out.

You took a photo of the wrong side

What does the business end look like? Could be the yoke seal or the pumpkin gasket
My bet is on the pinion yoke seal. If it is not dripping a lot, I would just check level or refill.
It doesn't take much lube to wet that thing all over over time

Maybe avoid 75W-Xx groil if possible

- Ken

 

[Astro14]

While that's pretty rusty, the housing is rather thick, and I doubt it's rusted through anywhere.

I would check the vent, and pinion seal, and brake lines for leaks right now. The mud daubers in VA do like to nest in lines, you wouldn't be the first, and a bad vent will force fluid out the seals when the diff heats up.

Clean it all up well and watch to see where the fluid begins to show up again. It's easy enough to just roll under this periodically to check.

 

[Gebo]

Pics that were requested..

 

[Gebo]

You took a photo of the wrong side

What does the business end look like? Could be the yoke seal or the pumpkin gasket
My bet is on the pinion yoke seal. If it is not dripping a lot, I would just check level or refill.
It doesn't take much lube to wet that thing all over over time

Maybe avoid 75W-Xx groil if possible

- Ken

I cannot see any leaks on the driveway where it's parked. I got you some pics

 

[mattd]

Did you check the vent?

 

[Gebo]

Could over greasing the slip joint cause this?

 

[Gebo]

Did you check the vent?

Not yet. Just trying to come down from the brake cleaner fluid high at the moment. I used 1 1/2 cans. The Red Stuff.

Gonna take it out for a spin and come back pretty quick. Just started my colonoscopy prep 2 hours ago and my wife told me to not get
too far away from a toilet.

That is next on my list. Thanks!

 

[zfasts03]

Sounds like you are going to have 2 leaky rear ends soon.

 

[spasm3]

Not yet. Just trying to come down from the brake cleaner fluid high at the moment. I used 1 1/2 cans. The Red Stuff.

Gonna take it out for a spin and come back pretty quick. Just started my colonoscopy prep 2 hours ago and my wife told me to not get
too far away from a toilet.

That is next on my list. Thanks!

Yes , you will have to sit out, the rest of this thread!