Transfer case leakin while Jeep is in motion

[Mud Chuck]

My transfer case was leaking so I had front output shaft seal, rear output seal, input seal replaced. No leak while the jeep was parked but when I drove it the t-case fluid was flying everywhere under the jeep and collecting in the pan. Any advice on where it could be coming from?
Thanks in advance

 

[superj]

not from me. thats crazy though. i wonder if a slinger got left out or something

 

[Bounty__Hunter]

Likely the transmission rear output seal if it hasn't been replaced. That would explain leaking when the transmission is pumping fluid.

The transfer case input fits into the transmission output seal and creates the seal.

 

[josue estrada]

im having the same problem

 

[Mud Chuck]

Thanks guys, I'll check those out....Let you know what it is when I find out.

 

[Syko]

Still could be the output shaft seals, and have the driveshafts slinging the fluid. Any way you could put it on jackstands and see if you can tell where it's coming from sitting still ?

 

[Mud Chuck]

Okay, so the problem was that when the seal was replaced the first time, the "bed" that it sits in was not completely clean and the first guy used too much sealant. Second time around the seal was correctly in place. No leak.

 

[Syko]

Okay, so the problem was that when the seal was replaced the first time, the "bed" that it sits in was not completely clean and the first guy used too much sealant. Second time around the seal was correctly in place. No leak.

Sounds like he cut the seal installing it, lol.. At least you got it fixed, hopefully for free right ?

 

[jfrabat]

I had a leak coming from the speedo gear housing; the O-Ring on the speedo had broken, and it spilled from there... But in my case the leak came from the rear of the TC. Just in case someone looks up this thread in the future, but glad to hear you got yours fixed.

 

[JohnnyO]

In my case the NAPA catalog lists the wrong seal. My mechanic replaced it twice (I work near a NAPA store so I picked them up myself), then he told me he'd get one right from the Jeep dealer, which fit fine and doesn't leak.

 

[mouse53]

I am on my third seal installed properly and still leaking. I checked the shaft surface for grooves and made sure it was the right seal, but still losing fluid all over that rear of the TJ. I am stumped.

 

[Jester32]

Is the transfer case half or rear housing leaking. Is there a worn t case bushing or bearing on the out put shafts. There's many common leaks on these cases.

 

[mouse53]

Is the transfer case half or rear housing leaking. Is there a worn t case bushing or bearing on the out put shafts. There's many common leaks on these cases.

The only place I see a leak is the seal. I checked all over the t-case, but found no other leaks. The oil on the outside is ATF so cannot be the trans which has 80/90w gear oil. Anyone know why they went to ATF in the t-case?

 

[JohnnyO]

Did you use a seal from the Jeep dealer parts counter or a parts store seal?

 

[Jester32]

ATF has great lubrication qualitys at all temperatures. Allows smooth shifts. And works with t cases that uses clutches inside. Same reason the use ATF in most manuals now.

 

[Jester32]

And is it rear output or front output.?

 

[mouse53]

I thank all of you guys for the input. The leak is at the rear seal, purchased 2 seals from NAPA, 1st was OEM as far as I know.

I have noticed ATF used in many applications now including my Nissan work PU. I just remember my older Jeeps using heavier gearoil in the trans and t-case. They also used to have manual hubs so you don't have to lug all the front drive stuff when you are on asphalt.

 

[Bounty__Hunter]

Remove both driveshafts and start the Jeep in 2wd, allowing the rear yoke to spin. Make sure it spins true and doesn't wobble.

 

[Jester32]

I would pay close attention to the bushing in the extension housing. If its worn to much fluid will get past it and leak. The bushing is like 2 bucks and takes half hour to replace.

 

[Bounty__Hunter]

I would pay close attention to the bushing in the extension housing. If its worn to much fluid will get past it and leak. The bushing is like 2 bucks and takes half hour to replace.

His TJ doesn't have the extension housing or the bushing that surrounds the slipyoke. The TJ 231 rear seal fits tightly around the mainshaft and holds fluid in even when the slipyoke is removed.