Transmission issue with 88 MJ AW4

[AF Comanche]

I've been having intermittent shifting issues in my 88 MJ. It started a few months ago and it left me stranded an hour from home. That day it started shifting sort of odd. Sometimes when I would take my foot off the gas or break to slow down and then try to accelerate, the RPMs would go up but the transmission wouldn't shift. I could take my foot off the gas and then try again and it would shift. Eventually when I stopped at a red light it wouldn't shift out of 1st gear. I had it towed to a shop and he kept it a week and couldn't find a problem. He said more than likely it just had a valve stuck and it became un-stuck before he test drove it. Now it's starting to do the same type of thing again. It's only intermittent, but sometimes when it downshifts, it doesn't seem to want to upshift when I accelerate and even seems to surge sometimes. I noticed it is worse when it's cold. Could this be a TCU or solenoid issue, or should I start looking for a new transmission? It has 159,000 miles on it.      

[Eagle]

Do you have a factory service manual covering the AW4? IIRC you can remove the fuse and use the shifter to control sifts manually, but you lose one-half of the 1st/2nd combo (don't recall which).

 

I'm also wondering if your issue is the transmission not shifting, or the torque converter lock-up going haywire.

[MuddFoot]

first change you fluid and filter. then get back with us 

[HOrnbrod]

^^  First thing is to determine if the problem is electrical or hydralic. Use the below to perform the Manual Shift Test.

 

[banshee]

Cool info to know thanks

[AF Comanche]

I checked the fluid back when it was doing it the first time and it was right on full, didn't seem burnt at all, and I didn't see any metal shavings in it. I'm going get the fluid/filter changed tomorrow!

 

That's great info Hornbrod! Unfortunately, I don't have a pressure test gauge. I will do the manual shift test though and see what happens. Thanks! BTW, what part of Alabama are you in?