Hi I'm new with transmission problems.
 

Hello everyone. I'm new to the forum and I hope I have the right place for the questions I have. I have an '89 DLX all-trac that I've had for 5 years now. I have recently changed transmisison fluid and put a new filter and pan gasket on.

Shortly after the transmission started acting up. If it is really cold outside it acts like its slipping and having trouble shifting, when it's warm it's not as bad. Once I drive it for about ten minutes it starts to do better with the shifting but after it warms up and comes off of choke and I stop it has trouble running but manages. 3 out of 5 times if I stop the torque converter locks up and the car stalls just like forgetting to hold a clutch in when driving a manual.

I don't understand why it would slip sometimes when I'm accelerating but lock up sometimes when I stop. The weather is going to be getting colder soon and I have no idea what to do. I've never torn into an automatic before, but I know people who have. Since I have an AWD I would imagine it would be a pain in the neck to tear it out because of a transfer case.

I've heard some people mention a torque converter lock up solenoid that might be the problem, but have no clue. Anyways nice to be apart of the group and any suggestions would be greatly appreciated. Thanks!

Was all the fluid changed, if not what color is the fluid now. Red, reddish, brown, black?

The differential may have its own fluid camber separate from the trans case which may use trans fluid or a gear oil.

Check for a trans model number which should be on a sticker some where on the car, drivers side door, glove box, inside engine compartment. Trans model number would start the letter "A" and should be A540H which is a variant of the A540E.

This trans model should have electric shift.

Might start by checking for any trans trouble codes which are two numbers such as 42.

Test trans O/D light for illumination by turning on ign key and turning trans O/D on switch ON/OFF to get light to illuminate.

If light OK, inside engine compartment there should be a small plastic box approx 1 x 2 inches long perhaps on drivers side strut tower. Inside the box are electrical terminals.

Turn on ign key and O/D switch on (light off), jump electrical terminals in box T1 and E1 with electrical wire or paper clip then watch O/D light.

If no codes stored O/D light will flash at stead rate.

If codes stored light will flash out the code(s) one number at a time, example 4 flashes, pause, 2 flashes, longer pause = code 42. When code(s) output is completed codes will repeat.

If codes post them.

As you state the converter has a lock up solenoid which could be stuck open or other issue.

When the trans acts up have you tried manually shifting the gears, starting out in 1st then as RPM rises shifting to 2nd, etc?

Check the above first then post back.

Access to the lock up solenoid should be possible without taking the trans out. Can help with some info on this.

If an internal problem requiring removing the trans the major work is removing the front axles, the rear drive shaft removal should be reasonable simple.