Where are common spots the transmission leaks from?

Astro

Astro

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Joined
Feb 14, 2020
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Virginia
Well I got to my jeep today for the first time since November, I bought it November 10th and left November 15. Ik it needed axle work but just got to my garage and now it looks like it's a rear main seal, and the transmission has a leak somewhere, at least she fired up the first time! Anyone know common spots the transmission leaks from, it looks like it is above the pan but well investigate more tomorrow! Glad she's not my DD.

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Is this transmission fluid? It could be the pan gasket, but it could also be the input shaft seals. Either way, your transmission is going to have to come out it looks like.
 
Chris said:
Is this transmission fluid? It could be the pan gasket, but it could also be the input shaft seals. Either way, your transmission is going to have to come out it looks like.
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Yea the big spot is transmission fluid, little spot is what looks like a rear main seal but I can get to that by just dropping the axle, which I was doing for a lift anyways. Is the input shaft seals from the motor to the transmission? I hope it's just a pan so I don't have to pull everything. Any good rightups for this, looks like it's time for some heavy duty Jack stands. If I have to pull it what else should I do when I'm there?
 
Astro said:
30RH
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There are 5 most likely points of leaks for the 30RH. The front or rear seals, pan, the vent just above the input shaft, or where the dipstick tube seats on the passenger-side of the transmission.

If the ATF level is not significantly overfilled that eliminates the front vent as a possible source. The pan can be seen well enough with the tcase skidplate removed so you could tell if it's the source of the leak. I wouldn't guess the pan is a likely source of the leak. That leaves the front or rear shaft seals as the most likely sources. But the transfer case could be leaking from its input shaft, or even where the speedometer gear housing is seated in the tail of the transfer case.

I'd likely remove the tcase skidplate to look things over, the source of the leak might be readily seen. If not at least clean everything up so you can look again after a week or two to see if the leak might now be readily seen since cleaning things up previously.
 
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Thank you Jerry that give me a good headstart, I well tear into it tomorrow, it hasnt moved in 4 months and been cold so I hope it is just a pan gasket that maybe shrink a little from the cold, worse case I gotta pull it. It seems to be coming from the front area but I'll find out tomorrow. Seems like my luck, didnt even get 100 miles on it since I bought it before deployment! At least I get to wrench on something!
 
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Update on the leak, I cleaned up everything and of course it now is not leaking but when I was cleaning the weep hole on the transfer case it had some around it, cleaned it up and just waiting to see if more drops out, also half way up the bracket between the transmission and transfer case, on the transmission side there was some fluid around the bolts. I also noticed some dryed up fliud around the transfercase output to the front driveshaft. There is some fluid at the bottom of the bell housing but that's oil from my rear main seal I believe. So hopefully I can just pull the transfer case and replace the seal from the transmission and transfer case. Is that able to be done without pulling the transmission? What else should I change on the transfer case when its out?
 
The tcase can be pulled without removing the transmission. Nothing comes to mind that would need to be replaced on your tcase, they're normally pretty reliable. Fresh ATF wouldn't hurt, any good quality ATF is suitable for it. :)
 
recommendations for good ATF, I think when it's out I well replace both output seals on it, I wish I had my lift already so I could put in the sye and driveshaft when it was out.
 
Astro said:
recommendations for good ATF, I think when it's out I well replace both output seals on it, I wish I had my lift already so I could put in the sye and driveshaft when it was out.
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Literally any decent quality ATF sold in an auto parts store will be fine, it really doesn't care and it's not fussy about the kind of ATF you fill it with. Not many lubricated components in our TJs are as unfussy about what they get filled with as the tcase is. I use ATF+4 in mine but only because ATF+4 what my automatic transmission requires.
 
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