Transmission Leak?

I have a 2022 TRD ORP with under 20k miles on it. The only mods are sliders, gas tank skid plate and aftermarket fog lights.

Last year, I noticed a small puddle of fluid under the transfer case. I took it to a dealership and they changed a seal. Fast forward 8 months (I was overseas), and I noticed the same fluid on the transfer case. There was no puddle on the garage floor yet, but the T case had a drop forming.

I took it back to the dealer and they said it was coming from the transmission. They changed both seals (I don’t know which seals exactly, they just told me they changed the T case and transmission seals to be sure).

I noticed today (about 2-3 weeks after the dealer changed the seals) that the same fluid is seaping again.

What could cause such a leak? If it’s not the seals, would the actual transmission housing possibly be defective?

 

I would demand complete new case assembly. Seems like the part must be defective - poorly machined mating surfaces?

 

So I got an “opportunity” to look at all these seals last summer. Based on what I saw, between the transmission and transfer case is an open void. There is one seal on the transmission that seals where the TC input shaft goes in. A leak here would be red transmission fluid, It would settle in the bottom of the void until it dripped out somewhere at the bottom. If your leak was not red, then it wasn’t this seal.



The transfer case itself has a seal around the output shaft, and a seal around each shift rail. The front bearing housing is also sealed onto the TC with an rtv type sealant. A leak at any one of these locations would also show up near the bottom of the case.


If you see evidence of leakage coming from the top of the TC that drips all the way down the side to the bottom, the leak could be coming from the shifter itself. That wouldn’t require removal of the TC to fix, but reinstalling the shifter can be done incorrectly, which can damage the shifter housing/cap (then spring can come off and smoosh itself into the shifter housing metal). Incorrect installation where the spring doesn't stay put will also prevent the shifter cap from cinching down and making a proper seal.



My guess is a bad sealant bead around the TC input shaft bearing housing or the the seal around the shaft itself. Or both, since replacing the input shaft seal probably requires removal of the shaft bearing housing.

Are you sure that oil staining is new leakage and not the original leakage?

 

Thanks, I'm pretty sure the staining you see in the picture was from the first leakage. Here is another picture I took right before going back to the dealership two days ago:

 

They said they were going to order a new whole front end (their words). I'm assuming they meant the front part of the assembly. I'm waiting for the part to come in, and they'll let me know when to come back to get it replaced.

 

It’s nice you’re not getting the run around. It would be nice to know what they are actually going to replace though, especially if you plan to keep your 4runner long term. Make sure you get a clear description, with part numbers ideally for future reference.