1993 transmission problem

[kaw2000]

I have a 1993 Grand Cherokee, last week the over drive would not engage most of the time. A couple days later the transmission started to slip. I changed the filter thinking it may be clogged , this seemed to take care of the slipping problem but after taking it out for a long test drive it occasionaly will not come out of first unless I put it in neutral and back in gear. Also the overdrive light remains on all the time.
I'm thinking the o/d light is a fault indicator as well as a o/d off light?????
My guess is that my transmission is toast and changing the filter is just compensating for a major problem.
I did disconnect the battery to clear any fault codes.
I'm a pretty good back yard mechanic but I'm an idiot about transmissions.
Thanks for any help.

 

[Bounty__Hunter]

There's a couple solenoids in the transmission that can be replaced that may take care of your problems. I'd find a mechanic familiar with Chrysler transmissions, it's a common problem.

 

[MudderChuck]

Shift Pointers

I'm assuming the 93 grand has the same transmission as the XJ does.

This is a pretty good place to start. Though the last time through, I did figure out that some of this guys stuff was theory and he'd never actually tried it himself. Seems about 98% accurate though.

The controller for the transmission is a separate unit the TCU and actually gets little input from your regular computer. Speed sensor, throttle position sensor, and a mechanical throttle position (cable) that inputs passing gear and pump pressures are most of the inputs. There is a switch on the brake pedal that disengages the torque converter lock on most models.

I have the schematics for the 93 some place if they would be helpful? Most of my experience is with the pre 90 models, but they are largely the same as yours.