Hello, new member. I was giving a 90 model Laredo 4.0 4x4 for some work.
It shifted OK for a while but was pretty soft. Now it has stopped shifting at all. Only has 1st and reverse. Fluid is good.
I am a ford guy and know very little about these trucks though I have worked on my sister's 90 2x4 several times.
I have rebuilt several small block Fords and one C4 ford transmission. If I understand correctly this is a AW4 tranny in the Jeep. Are these things fairly easy to rebuild for someone that has done a little mechanicing?
I know it doesn't have a vacuum modulator, at least I can't see one but is there anything else with these trannies that would keep them from shifting and not be an internal problem?
Any help?
Thanks
Clint

 

The one thing i found that caused mine not to shift was the tps,it would not shift until about 4500 rpm,I replaced it and it works fine.

 

That sounds incouraging. TPS? I take it that is a transmission computer? I did not take it up near that high of rpm's when I was checking it out so maybe there is hope. I'll do a search for the TPS
clint

 

Throttle Position Sensor....yeah, that is probably your ticket.

 

With the engine running I am getting 4.75 volts between a and d on the 4 way connector. I get zero volts between b and d. So am I right in thinking the TPS is bad? I adjusted it around and still didn't get any voltage across b and d. This would be very good news if that is the only reason it stopped shifting. It never did shift very well. I was way soft but the F100 I drive everyday has a shift kit in it so I can't be sure what is too soft anymore.
Thanks for any help
clint

 

One thing that bothers me though. The transmission would'nt shift manually either. Would the TPS cause that also? If so then that has got to be the problem and I'll see if I can either get one from the pull a part or a new one depending on price
Thanks for any help
clint

 

vacume solinoids in trans can cause this, its a four pack int he bottom of the trans can be removed with just pan removal, I have pulled from the JY and been fine

 

you can check the tranny by unpugging the transmission control unit under the dash on the passenger side. You should be able to shift all gears if it is mechanically sound.

 

Thanks, I'll give that a try before I spend money on the TPS thanks for the help about the solenoids also
clint

 

Unplugged the tranny computer and I can shift it manually. YAHOO!
I'll hit the pull a part tomorrow and hopefully find a new looking TPS to put on there. If not I'll buy a new one. I have had luck on stuff like that in the past when gathering parts for my F100. Somebody goes through a lot of throwing parts at a truck and finally get tired of messing with it and have it hauled off. All kinds of new parts still on it.
Thanks for all the help.
Clint

 

Bought a used TPS from the local pull a part for $7 and put it on today. Transmission shifts like it should now. Thanks for all of the help
I had visions of having to rebuild the transmission. Glad it was so easy of a fix
clint

 

this is the correct advise

 

Posting it my garage over workbench...............

 

This might should be a sticky.
One time after I bought my dad's old 88 Lincoln Town Car for a road car when I was on the road all of the time the Transmission acted like it was tore up. Slipping, grinding gears etc. I thought I was 300 miles from home with a tore up tranny.
I called an old timey mechanic I knew and he told me to check the 11 cent rubber bushing where the AOD Throttle Valve cable hooked to the Throttle body. Sure enough it had broken and slipped off letting the cable fall loose. Next day I went to the local Ford dealer and bought that 11 cent piece of rubber. The old timer working there told me he hated to think of all of the Ford AOD's that have been rebuilt and all of the people paying for a rebuilt transmission when all that was replaced was an 11 cent piece of rubber.
Thanks for all of your help
Clint

 

the jeep aw4 works a little different than the ford dos but I know what you are saying