Mechanical problems:
* Worn friction discs or steel plates
* Faulty solenoids
* Clogged valve body
* Problems with the pump
* Torque converter wear
Electrical problems:
* Faulty speed sensor
*Faulty throttle position sensor
* Faulty Transmission Control Module (TCM)
*Wiring problems
Fluid problems:
*Low transmission fluid level
* Contaminated liquid
* Fluid leak
Other reasons:
* Improper driving (rough driving, towing heavy loads)
* Driving with a faulty engine
* Insufficient maintenance
* Problems with engine mounts