There is no Transmission Control Module (TCM) on the 3 speed (31TH) Transaxle. The "studder" or shudder may be coming from the Torque Converter. There is a Torque Converter Clutch (TCC) operated by a solenoid controlled by the Powertrain Control Module (PCM). This would be an internal issue and would have to be replaced. Depending on the mileage of your vehicle, you may want to consider replacing the transmission with a rebuilt unit. If you have a dealership install a MOPAR remanufactured transaxle, you will have a 3 year warranty on it. It may cost alittle more, but it is worth it. Your choice.