Xjriding

Wassup guys I'm new to this forum and don't know where to start about my jeep and I really need someone's opinion before I take it to a mechanic and possible get screwed over since I have a feeling it's might be something simple to fix like a solenoid because it shifts into all gears still and I'm pretty handy when it comes to fixing my cars so I'm gonna go straight to the symptoms... first it feels like it's slips on first gear because my rpms are almost at 3k and the jeep ismoving like if it was at 1k after that it shifts fine anddownshifts fine as well and feels strong ... second, it would gush out a lot of tranny fluid if I would drive it on the freeway and a lot of white smoke would come out due to the fluid hitting the exhaust and if I let it cool down for like 30 min it would run normal again but when I park it it has no leaks and if I drive it on the street slow it wont spill any fluid and run fine... also once it starts leaking the fluid it feels like it goes to neutral and doensnt go into any gear until it stops moving and just idles and lastly when I turn it back on it automatically revs up all the way until it redlines but i turn it off before it does hit the redline and I let it cool down.... so then a mechanic diagnosed it and said I needed a complete rebuilt but was too expensive so I took it to another mechanic and he told me to replace the transmission cooling lines because they were mostlikely clogged so I did that and it still revs up on its own once it gets hot again and I have to hit the brakes so it won't take off on me.... one of fhe cooling lines had a pretty good amount of dirt or atleasf it looked like that...before I replace the cooling lines the first gear would slip even if I put it in first gear manually but now that I replaced the lines it takes off fine in first gear if I put in in manually sorry for the long essay but I really feel like I need to explain all these things to get a good opinion from you guys.... please help and let me know what is wrong with orif you guys have any tips thanks for reading this thread any opinion helps thanks.

bad_idea

First thing to do. Punctuation. Had to read that three times to understand what you are saying.

Sounds like the transmission is overheating. Does the engine overheat? I suggest you do a test to identify the overheat source. Get a non-contact thermometer (can get a decent one at Harbor Freight), go for a drive. When it gets hot, stop vehicle and check the temperature of the transmission pan, each line, and the cooler in the radiator. I understand you replaced the transmission lines, did you replace the cooler or at least flush it? If the lines were plugged, I would say the passages in the trans are also.

Next question, where did the trash in the lines come from? If the lines were plugged, that was likely friction material and other vital internal components from the transmission. I would start looking for a used transmission. They can be had with low miles for a few hundred dollars. Not hard to replace a transmission, just a but involved.

Xjriding

Sorry about my punctuation i been told it sucks lol and thanks for still trying to help. The heat source is coming from the transmission, the first mechanic I took it too diagnosed it said my tranny was running very hot and my fluid smelled like burnt. Now that I think about it I did notice a change in color in the radiator water it went from green to a muddy brown after I changed the cooler lines and the dirt that was stuck in them was on the radiator side of them but not completely plugged. You think flushing the radiator is worth the try or just swap the tranny? Do you know any other cheap fixes I can try before swapping it out?

I was thinking of just replacing the tranny for a low mile one like you said but I just feel like it's a toss up when it come to that since it can be a a bad tranny too. Under how many miles do you suggest getting a used tranny?

dzywicki

I'm going to add my experience with a leaking AW4 transmission.

I have a '99 with AW4 automatic transmission. I was experiencing white smoke from ATF hitting the exhaust. It was fine until the transmission heated up and then it dripped like a sieve. It dripped from the bellhousing right onto the exhaust.
I determined it was the front input shaft seal. I dropped the transmission and replaced all the seals I could. total parts for seals was ~$50 if I recall correctly. That was 30k miles ago and it's been fine ever since.
That front seal was completely hardened and once the fluid would heat up, it would rise to that seal and leak out pretty quickly. So if you are thinking one of those stop leak products will help, it wont.

I reread you second post and it almost sounds like you are mixing coolant and transmission fluid which would indicate a problem between the radiator and trans fluid cooling tank. If you have brown colored coolant, I would flush that. You can refill with distilled water to test it

bad_idea

Did you see the radiator fluid green and shortly later it was brown? If so, then the radiator is likely bad. The transmission cooler within the radiator is likely ruptured, mixing transmission and radiator fluid.

Or are you assuming it was green and it was brown when you checked it? If so, then coolant gets a brown color with age. Not a big deal, should be changed, but isn't part of the transmission problem.

As far as 'low mile', hell if I know. I would typically say under 60k, but that was before I got this XJ. Mine has 235k on the original transmission. Would likely say 150k, but thats just a WAG, not based on solid experience with AW4s. Hopefully someone with more experience will weigh in.

It may be a good idea to replace the radiator, especially if the engine is overheating also. If the engine isn't overheating, then I would suggest you get a external transmission cooler. Plumb the transmission into the external cooler, bypassing the stock cooler. Most will tell you to keep the stock cooler in the loop, I suggest you bypass it temporarily to help troubleshoot your issue. The ZJ cooler is a good, cheap cooler if bought used. If buying new, I like my B&M cooler. An external cooler is a good addition if you plan to do any wheeling with it, so it isn't a total waste of money.