I have 2003 Caravan that has a bump shift from 4-3. It does not happen if the gear selector is on 3. Happens around 45 kph (25 mph). I you are coasting then it is not too bad but if you are braking quite hard then it is rough. Or if you are a highway speed at move the selector from D to 3 then it is rough too.

Had the fluid/filter changed 3 months ago with ATF+4, no shavings in the pan.

So from searching the forums it looked like the TCM had to be reflashed.

Took it to the dealer to be reflashed, they tried for 1.5 hours and two scanners to update the software but the TCM would not accept the update. They are telling me that most likely the TCM need replacing. Does this sound right or should I take it somewhere else.

Has anybody had any luck buying a TCM online and installing it themselves?

 

Welcome to DF
I have had some problems doing flash on the pcm. Found out the ABS module was locking up the controllers to the point that they wouldn't accept any updates. I would unplug the ABS module and the controller then accept an update.

 

That's interesting, I guess I will ask if they tried that. I sure don't want to buy a new TCM if that is not the problem.

 

Well I asked them about it and they responded kind of smugly "The problem is with the TCM not the ABS, ABS has nothing to do with it" and insisted that it had to be a faulty TCM. So they want $378 for the part and 1.5 hours to install and program.

I am looking at getting one online that comes programmed to the VIN and with latest software from Chrysler. Has anyone ordered these online before?