AW-4 Problem

I've got a 4.0L '98 Cherokee with the AW-4 tranny, Up Country packeage including the small external tranny cooler. 100k miles on it.
I overheated the transmission for the first time this summer (my fault, driving way to hard up a long, major grade) to where it leaked transmission fluid onto the exhaust...lots of smoke.
I took it into the dealership and had the transmission flushed. The problem got much worse as it started to smoke again with only a minor 1,000ft. elevation gain. So, I immediately took it back (100 easy miles later) to have the dealership tell me that they overfilled it. They took out the porper amount of fluid, and off I went.
Now, the tranny still blows out a little smoke when driving up and over steep mountain passes (3,000 ft), which it never did before the original overheat this last summer.
The dealership did not run a pressure test to check for any restrictions.
Does anybody have any suggestions as to what I should look into, as well as any possible scenerios that might have happend?
I hate to think that I might have ruined my transmission.
Thank you for any feedback,
Steve

You should probably verify that the dealership put in the correct fluid. They have a bad habit of putting ATF4 thinking it's a Chrysler made tranny. It's an Aisen-Warner tranny that requires Dexron-IIe or compatible. Your owners manual will tell you how to check the fluid level, btw.

Yep,
I've already done both and I still don't know what else to look at.
Internally, what could have gone wrong?
Thanks,
Steve

Anybody....pleeeaaassee

Where does the smoke come from? Dipstick?

The smke comes from the oil dripping onto the exhaust, which I can observe, I cannot not locate where on the tranny it's coming from.
The last two times it did so, I found no evidence of oil pushing it's way out of the dipstick. The dealership told me that their is a "vent" somewhere on the tranny that is specifically made to relieve pressure if the fluid get too hot...Is this true?
I cannot find where this "vent" is...nor can I guess why it's happening now anytime I climb over some normal mountain pass.

this might sound dumb, but I had a simmilar problem with my '88 XJ.I over heated it, had the tranny fluid flushed. it still leaked. it looked like it was a leaky torque converter because that is were it was coming from. I think it was the front seal ( that is what I have read gives way if you over heat the tranny) It was horibble. driving down the highway I could see the cloud of smoke behind me from burning off the exhaust. I took it to a Tranny guy ( vary reliable and knoledgable) he thought it could be something internal. Not wanting to spend the money on rebuilding an AW4( mostly because of the sticker shock when I'm used to paying between $250 and $300 CND for rebuilding torqueflight 727's) and not having time to do a tranny swap. I just Parked the XJ and drove another one of my cars. In early November '06 ( after being parked for just over a year ) I decided to start using the XJ again and dreaded the tranny leak. But this time had the time to do a swap . I decided to try driving it first. and Guess what NO TRANNY LEAK!!! My gues is that once you blow the seal from overheating the AW4, it needs time to reseal itself or you need to reseal it. If you do not want to spend the money to replace the seal try some "Lucas Oil's" Tranny additive. or some other type that claims it can help with tranny leaks like GUNK Hope this helps

Rebel68,
Thanks for the reply. I really appreciate your personal insight.
Is the seal you despribed, the one that lets go if something gets damaged from overheating? Are there any other seals or the like that are known to be possible culprits?
Thanks again,
Steve
ps. Anybody else have any kndowledge that could possibly help me out, I'd appreciate it!

i had the same problem and it really does sound like the front seal, mine would smoke only on the freeway, and after on normal streets it wouldnt smoke and I couldnt find the leak... i looked and past the bell housing the trans didn't leak, so if I were you I would take the inspection plate off the front of the trans (like four bolts) and check to see if there is a pile of fluid there at the bottom of the bell housing. that was the indicator for me on what it was on my 95 xj. and about the vent, its usually on the very top of the aw4 and the passenger side and it is hard to see. as the internals are concerned as long as you changed the fluid right after the trans overheated and (its the right fluid) also if its shifting ok like normal and not acting funny I wouldn't worry all that much.

DurbElites,
Thanks for your post. I have yet to find the "vent" and your description tells me why...
I think I should degrease as much as possible and go up the local mountain where it always smokes a little, and immediately try to find the leak source (I tried this several times already, but no luck).
Because you as well as others have repeatedly brought up the tranny fluid question, I have to ask, "Is there any way for me to find out if the dealer is being honest with me about using the right fluid?" Can I tell by looking at the fluid?
Something that might also help you knowledgeable guys: After the second trip to the dealership and he removed excess fluid, he added a mopar anti-foaming agent...
Thanks again, all.
Steve

There is a vent at the top of the transmission that lets air in and out as the tranny heats up & cools & atmospheric pressure changes. There may be another vent for when the tranny is over serviced, but I can't say for sure

Are you sure it's tranny fluid and not a somewhat common valve cover leak, oil filter adapter leak, or engine rear main seal? If it's motor oil also check out the crankcase vent lines to make sure they are not plugged. If it's indeed redish fluid, then pull the inspection cover and look for oil inside the bellhousing which would point to the front tranny seal. As I recall the tranny vent line runs up onto the passenger side of the firewall. If it's missing then you may be losing oil out the top of the tranny. Also if they pulled the transmission pan, it's possible they messed up the seal where the dipstick tube goes into the tranny pan.

Whoa...now there is some great info....thanks everyone.
I need to fish my FSM out of my storage after I get the new alternator installed, and find out where this inspection cover is at. All of this info is going to help me out.
Only one thing left for me to find out before I tear into this or lose my hair trying: Is there a way for me to tell what kind of fluid the dealership might have used for the flush ? They talked me into a flush instead of a filter screen change
Thanks, again everybody for your help.
Steve

The inspection cover is the thin flat piece covering the lower front part of the bellhousing.

If the dealer refilled the tranny, it's very likely that they used the wrong fluid; they have a habit of filling it with the ChryCo (ATF) stuff instead of the correct Dexron fluid.

Thanks for the pic, Yucca-Man. That sure does help.
I'll take a look at it over Thanksgiving. It sounds like everyone is in agreement that the dealership put the wrong fluid in when I paid for a flush.
I'll take it back and ask them to flush it with my own supplied tranny fluid (on them..) since there might not be any other recourse providing I don't find any signs of leaks from the front tranny seal. If they refuse, I'll go ahead myself and do the 4-5 drain/refill procedure myself to be sure.
Thank you everybody for your time and help. All the browsing and this posting on this site have been a learning experience. When I finish finding out the cause, I will post the findings.
Cheers,
Steve

Wow that picture really does answer a lot of what I had to ask.

However, here's my situation.

Last week...tranny overheated after sitting in bad stop and go traffic. The type of traffic where you get going just fast enough to hit 2nd gear and then you gotta come to a stop again.....I did this for over an hour.

After finally clearing the traffic, I got up to speed for about 2 minutes untill I got to my exit, and as soon as I let off the gas to slow down, the entire jeep "bucked" real bad, right as it came out of overdrive. I looked in my rear view to see nothing but smoke behind me (couldn't tell what color as it was night time) and pulled over immediately.

At first I thought motor oil, but it sure didn't smell like oil, and my oil level was fine. I let everything cool off about an hour before heading the 30 miles back to school with no problems, and then drove it 3 days later the 90 miles home with no problems.

This week alone i've put 600+ highway miles on it (three trips to Charlotte and back) with zero trouble out of it....until today.

I got home from charlotte and was running some errands around town. I began to notice that the idle was higher than normal when stopped...say for a light or a stop sign....but not every time I stopped. I could just tap on the gas lightly one time and the idle would come back down. I stopped to get some gas and the idle was way up....about 1100-1200. Couldn't get it to come back down, so I just shut it off and went about getting my gas, thinking it would reset when i restarted...much to my surprise it didn't, but the "gas tap" trick worked once I restarted the engine....that was the last of the high idle so far today.

On my way home finally it began to come out of OD hard again...but not nearly as bad as last week. I also didn't see any smoke today...which was a good sign.

However, when I got home I immediately smelled burning something and lo and behold, it's leaking transmission fluid again, although not as bad.

I know i need to change my fluid, especially after last week's episode. But I have a hard time seeing how it overheated today....I can definitely understand last week.

As far as the idle sit. goes, i'm thinking maybe a dirty TPS (i've had the CEL come on for it ONCE, and that was back in March) or some other sensor. The TB is pretty clean as I took it off about a year ago and cleaned it out real well.

Any suggestions from anybody? Thanks guys.

That is exactly what your problem is a faulty TPS. My brother with his 2001 XJ had THE EXACT SAME PROBLEMS that you are having. It burped on the freeway and overheated the trans and fluid came out of the dip stick and all over the hood and hot engine components smoke everywhere.

Change your TPS - Change your transmission fluid (Dextron III) and filter and you will not have the problem anymore. That is what we did to his 2 weeks ago and just got done towing a trailer w/ 2 quads home form the desert in Cherokee 100 miles w/ no problems.

fdsa487

Been driving it around tonight after it cooled off....put another 50 miles on it on the highway after sitting for about an hour and a half with no issues.

The fluid is not coming out of the dipstick, however it is coming out of the vent on the tranny.

I did get a code a LONG time ago for a TPS issue...but that was back in March and was a fluke...have not had any issues since then.

Might go ahead and replace the TPS and give the throttle body a good ole fashioned cleaning.

I'm most certainly replacing the filter and changing the fluid in the tranny sometime this weekend, if not very early next week. Kinda in the middle of moving to a house thats 30 miles away from where I am now....so gonna need the heep to haul stuff this weekend.

I'd like to flush out the tranny, but I supposed replacing the filter and replacing the tranny fluid will do for now....better than nothing. Will probably also hit the tcase while i'm buying ATF anyways.

Well I was driving down the highway running about 70mph and the Jeep began not staying in a gear. Pulled off the highway, shut it down, restarted it, and all was good for the rest of the day.

The Jeep has done this ONE other time, back in March, but it threw a code for the TPS....today NO codes were thrown.

It's sitting up at my dads house this week untill I can get a chance to work on it. I've got a 30 mile commute for work (one way) beginning this week and can't afford to have it die on me on the way to work.

Looks like a new TPS is in my future.