Common reasons:
* Incorrect maintenance (failure to change automatic transmission oil and filter)
* Using poor quality or unsuitable oil and filter
* Automatic transmission overheating due to excessive load or cooling problems
* Driving in low gears for long periods of time
* Aggressive driving style
* Wear or damage to automatic transmission components
Mechanical reasons:
* Wear or damage to clutches and steel discs
* Faulty or clogged hydraulic valves
* Damage to gears or bearings
* Oil or air leaks
* Broken or damaged gear shift cables
Electrical reasons:
* Faulty automatic transmission control unit (TCU)
* Failure of input and output shaft sensors
* Faulty wiring or connectors
* Problems with the battery or generator that affect power to the automatic transmission
Software reasons:
* Bugs in TCU software
* Incorrect software update
Other reasons:
* Engine problems (eg faulty fuel injection system)
* Malfunctions in the cooling system
* Worn torque converter clutch
*Defects in design
* Poor quality components