Trx Leaking differential

Lsrose · Aug 20, 2021

Has anyone had the rear differential leak in this spot? I just got 1k miles on it never been offroad or anything. Looks like a tiny pin hole in the metal but no puncture marks or anything just a little divet in the metal?

Two · Aug 20, 2021

Sorry, but I can't even tell if I'm looking at a rear axle in the first photo.
But it does look like more than a minor leak, on whatever the oil is on.

RobR651 · Aug 20, 2021

I’m with @Two looks like you’ve got a leaker but I have no idea what that first photo is either.

OnTheReel · Aug 20, 2021

Looks like the bottom of the pumpkin. I saw those those two ribs on mine when I was doing some rust-proofing.

Probably a casting flaw. No other reason it would leak there. If it is indeed leaking from there.

Two · Aug 20, 2021

Yes, that could be what it shows. But still impossible to tell where the oil's coming from.

I'd clean everything off, then drive a bit and see where it starts.

Two · Aug 21, 2021

After thinking more about it, the most likely source would be the pinion seal. Not that a new one should be leaking, but stuff happens. And it's a cheap and easy fix.
Or maybe the cover isn't tightened correctly? That'd be a really easy fix.

Not likely, it's coming from the vent hose. That would probably require that the diff is overfilled, which is extremely unlikely since almost all of them seems to be a bit low these days.

Anyway, that vent hose deserves some attention regardless, I think. Not that I plan to go into deep water, but as it is, the cap at the end is almost down at axle tube level.
I'd like mine to be at least above the top of the frame.

OnTheReel · Aug 21, 2021

Pinion seal would definitely make more sense. Obviously it could run down to the bottom of the diff like that and fool someone. Don’t think there’s a very high likelihood of a casting that thick being porous enough to leak.

BusaDave · Aug 21, 2021

Go under---hose it down with brake cleaner then see where it is coming from after you drive it. Hot oil plus being blown by air at speed can make it look like the whole axle is leaking....

I am thinking seal.

Steiger · Aug 21, 2021

Pinion seal is most likely but as has been said, need to clean it all off first and take a short drive

Lsrose · Aug 29, 2021

Not pinion seal. Took it to the dealer they agreed. Its a pinhole in the casting. Should have the new axle this week and friday should be able to have it swapped so we will see how it all goes.

Steiger · Aug 29, 2021

That is really odd. I have never seen an axle leak because of a porous casting. Thankful that they are able to source a replacement so quickly.

Two · Aug 29, 2021

Steiger said:
That is really odd. I have never seen an axle leak because of a porous casting. Thankful that they are able to source a replacement so quickly.

Just about anything is possible. At least in theory.
I would've never guessed it was a pinhole. Would love to see a photo of it.

Steiger · Aug 29, 2021

Two said:
Just about anything is possible. At least in theory.
I would've never guessed it was a pinhole. Would love to see a photo of it.

Agreed! I was as surprised they had an axle available as I was that the housing is leaking

Two · Aug 29, 2021

If it's only a new housing, it may be the same as in a regular 1500 with the max tow package. Maybe.

Steiger · Aug 29, 2021

No the TRX rear end is massive compared to a regular 1500.

Two · Aug 29, 2021

As I recall, the max tow version has a 60, with 6-lug.

OnTheReel · Aug 29, 2021

All the 2019+ Rams are 6 lug. Not sure if the axle housing for the normal Ram would have the mounting bosses for the third shock at the top.

Either way, if they replace it as an assembly this is gonna cost them some $$$.

Two · Aug 29, 2021

OnTheReel said:
Not sure if the axle housing for the normal Ram would have the mounting bosses for the third shock at the top.

Good point. We get their anti sway bar brackets, but that doesn't mean they get that upper shock mount.

l2azorback · Aug 30, 2021

Lsrose said:
Has anyone had the rear differential leak in this spot? I just got 1k miles on it never been offroad or anything. Looks like a tiny pin hole in the metal but no puncture marks or anything just a little divet in the metal?

Is it running down to the bottom from the Pinion Seal?

Lsrose · Aug 30, 2021

l2azorback said:
Is it running down to the bottom from the Pinion Seal?

If you look at the bottom of the diff (which these are dana 60s) there are 2 fins and a groove between them and it is up in the groove so no oil on the outside of the housing or anything just directly from below