aw4 leak

My 91 XJ has recently developed a weird leak from the transmission. Seemed to of started after having my motor mounts replaced. Anyway it is a 1991 4.0l aw 4. Doesn't noticeably leak around town or even at 55 mph. But around 65 MPH it starts puking fluid out of some where onto the exhaust everytime the tranny shifts. Makes a bad smoke screen. The motor doesnt use much oil and doesn't have any over heating issues. The motors stays fairly cool. Also noticed that when in 4wd the tranny starts puking some fluid as well after alittle while. The tranny shifts great, don't have any other issues then this darn leak.

Also it has 31's and stock gears...

Im assuming the undercarriage is saturated. What i always do is spray degreaser underneath the car. Then pressure wash the fluid off. You can just use a hose. Then i drive the car for a short distance and crawl back under to pinpoint where the leak is from. Also since your xj is 4wd the fluid may be coming from the transfer case. If you can give us a general vicinity it will be easier to fix

If it's overfilled or gets too hot it will spit out the vent tube on the top of the trans, usually the passengerside.

Well the under carriage is completely saturated. It only does it when the tranny gets hot such as when I am running the dunes or driving on the freeway for awhile. It seems to leak roughly from the front of the tranny some where. But the trick is it seems to only be leaking when the tranny shifts, that seems to be the key. Like fluid moving through something when shifting.

MJR said:

If it's overfilled or gets too hot it will spit out the vent tube on the top of the trans, usually the passengerside.

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Right I have read that. It is not over filled. Even when the fluid level is low it will pump out fluid when it shifts.

I guess I have two questions right now:

1. Does anyone have a picture or at least a good description of the tranny vent/location?

2. Would a clogged filter cause the tranny to over heat?

You'd have burnt fluid if it got too hot. the vent is a little metal tube on the top of the trans near the bell housing (very hard to see).

Are your trans cooler lines leaking/pinched/blocked?

The transmission dipstick can be pulled out through the top in the engine bay. just yank on it decently hard and it should come right out. There is an o-ring at the base of the tube where it connects to the transmission pan.

I had a similar problem to this where the tranny would only leak when the jeep was moving. i had pinched one of the tranny hard lines but the fluid would come out of the pan gasket. I fixed the problem by cutting out the bad part of the hard line, flaring the ends and clamping a rubber tranny line in it's place. I also dropped the pan and changed the filter while i was in there and resealed. fixed the problem right up. hope this helps

mnaemark said:

The transmission dipstick can be pulled out through the top in the engine bay. just yank on it decently hard and it should come right out. There is an o-ring at the base of the tube where it connects to the transmission pan.

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The trans dipstick tube has a bolt (1/2"/13mm I think it was) holding it to the bell housing.