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Electronically-Controlled Transmissions

My first experience with an electronically-controlled automatic was with my '02 Dodge Caravan. When I changed transmission fluid and filter, using the specified Chrysler ATF+4 fluid, the trans lost its mind. When the electronics woke up to new operating parameters, the transmission started behaving badly: harsh, almost damaging 2-3 downshifts, flaring upshifts, etc. Sometimes when the lever was placed in Reverse position to back out of the garage, the trans did not engage at all. Had to take it to the dealer to re-program the controller (under warranty, the first time).

The second fluid change, quite some time later, resulted in similar behavior. Had to pay the dealer, that time, to re-program.

At 135k miles, instead of dropping the pan, I used a suction gun down the dipstick tube to draw out a gallon of old fluid, and re-filled with new ATF+4. This time, no problems, only a partial fluid change. I’m trying to keep this vehicle on the road for a long time, and it has been very reliable, except for the ridiculous, unacceptable behavior of the transmission electronics. I also have to wonder about the future with the '10 Ford Fusion.

Anyone have similar experience, or information/assistance to offer?

(Please, no comments about changing the fluid too often. I’ve worked with vehicles and industrial machinery for long enough to know that “maintenance-free” is not a real-world option).

DYI automotive maintenance is becoming a lost art. You are expected to return to the Dealer for ALL your maintenance needs…Electronic controls that require proprietary equipment, software and knowledge to maintain and service are becoming the norm…When these vehicles 'trickle down" into the secondary and tertiary markets and dealer service is out of the question, they get scrapped when problems such you describe arise… People with limited incomes will gravitate towards vehicles with a minimum of electronic controls or “Dealer Only” service requirements…This is the main reason “Luxury Cars” collapse in value when they hit that 100K mile mark…

U dropped pan, changed filter and trans went crazy? I have never run across a trans that needed to be reprogrammed after a simple service. I have owned several Chrysler fwd cars and done the same service and had no such issues. Maybe you are unlucky?

If you started the vehicle whilst there was low or no transmission fluid it, then the transmission will default to limp home or panic mode, and it will attempt to raise the line pressure to theoretically keep the transmission fluid circulating. This will cause hard shifting and other problems.

I had a '90 Plymouth mini-van, a '93 Caravan, and now have an’09 Caravan and never had the problems you mentioned. (or any other problems for that matter).