I think i may have tranny problems?

[greenchevy]

I have a 1989 Jeep Wagoneer limited. Just recently had the water pump go out. I figured since i always have problems with the cooling system i would change it over to a 92 cherokee open cooling system. When the water pump went out then this shifting problem was starting.The first shift is good then the second shift is ok then it wont shift the third time. It just starts to high rev rpms then it will slow down then the rpms will drop to 1000rpms. I figured this was because there was air in the block. If you drop it in 3rd gear it will go away. What maybe causing this? I had the transmission rebuilt 3 years ago. Could it be my Transmission control module? How can i test this?I've been reading online and some info i got was if the transmission is over heating that it will intentionally lock itself out of 4th gear/overdrive so it doesn't get hotter.

[alwaysxj]

i would maybe take off the NSS and clean it. i think Melissa did a right up on this...
if that does not help maybe it is a TPS not shifting right...

[Thomass]

The AW4 manual says the following about such a fault.:
Electronic control problem ... repair with OBDII "tester"
Valve body faulty ... repair Valve body
Solenoid fault ... replace solenoid

They also write that if the tranny oil became overheated by faulty oil cooling,
the oil quality should be checked and possible replaced together with the filter.

Then I should also check the throttle cable adjustment

Does it engage in reverse ? , is the car blocked if it is in P (not able to push the car)

you might also want to read this:
http://www.allpar.com/fix/trans.html

[greenchevy]

Tranny works fine until It warms up. Once the tranny is warm it locks it self out of overdrive. So now i'm wondering what is causing it to get hot and lock itself out of overdrive. It works in every gear but overdrive. I don't think it's the tps since the jeep runs fine for a little bit. The trans oil doesn't look burned. I'm way over due for the trans fluid to be changed.

[W.O.R.P.Offroad]

sounds like its either a fluid or temp prob. any chance you could have pinched a tranny line that goes from the tranny to the cooler? they run right above the pass side upper control arm mount. i have seen the mount hit them alot and flatten them and people didnt even know it. it caused it to restrict the flow and get hot

[greenchevy]

I talked to a guy i know at carquest about it. He has the same year jeep. He said that his jeep did the same thing. He said to change the fluid and while i had the pan off unbolt the solenoids and clean them with brake cleaner. He said the screens on the solenoids get clogged with crap and when the tranny warms up the stuff on the screens make it clog up. So I'm going to change fluid and clean the solenoids up and tell everyone what happens. Thank for the help everyone.

[rguignard]

I talked to a guy i know at carquest about it. He has the same year jeep. He said that his jeep did the same thing. He said to change the fluid and while i had the pan off unbolt the solenoids and clean them with brake cleaner. He said the screens on the solenoids get clogged with crap and when the tranny warms up the stuff on the screens make it clog up. So I'm going to change fluid and clean the solenoids up and tell everyone what happens. Thank for the help everyone.

mine did the same thing ck the solenoids while you have them out just use the battery from your jeep and 2 wires one to pos and one to neg just make sure they click when you add power. put the ground to the bolt hole and add power to the place that the wire went to :thumbsup: i had 1 bad one. i hope this helps you

[greenchevy]

though my nightmare was over but its not. I did everything and changed the fluid 2 times now I'm going to do it for the third time now. The tranny sometimes drives fine with out slipping out of overdrive and sometimes it will just start slipping. It doesn't have a consistently of when it will slip. I'm going to drop the pan, check the solenoids, and clean then again. Hope this is the last time. With the fluid change it has been working a million times better. It used to slip out of overdrive every time you drove the jeep. Would a transmission flush work better with a machine? I can't think of anything else. :headshake:

[greenchevy]

OK i think i fixed it. There are two steel lines on the valve body. One of the lines fell off when i dropped the pan again and the other was close to falling off. Put the lines back in and tighten everything up and put new fluid in. It started up better then before. Now to see if it doesn't slip out of overdrive anymore. I think what was happening was that when it needed more fluid in the transmission it wasn't getting it since the lines where so loose. The fluid sucked in the valve body was just being shot back in to the pan instead of in to the transmission, causing it to get hotter then normal causing the transmission to slip out of overdrive so that it wouldn't damage the transmission more from the heat.

[rm2406]

Old thread but have same issue... Curious if tightning up the metal tube lines fixed the problem??? Hows it doing now???

[cantab27]

bang up a new thread Rudy,,,...with your trans problems.....fresh thread fresh ideas