Possible reasons for heavy automatic transmission shifting:
Mechanical problems:
*Low transmission fluid level
* Contaminated or degraded transmission fluid
*Wiring or hydraulic problems
* Faulty Transmission Control Unit (TCU)
* Worn or damaged friction discs or bands
* Faulty fluid coupling
* Clogged oil filter or lines
Electrical problems:
* Faulty input/output shaft speed sensor
* Faulty engine speed sensor
* Faulty transmission fluid temperature sensor
Software problems:
* Bugs in TCU software
* Incorrect or outdated TCU software
Other possible reasons:
* Clogged transmission oil lines
*Low battery voltage
* Faulty gear selector
* Faulty ignition switch
* Play in the transmission or driveshaft
* Faulty drive shaft
*Car software problems
Diagnostics and repair:
To diagnose and repair heavy automatic transmission gear shifting, it is recommended to contact a car service center. The technician will perform a transmission diagnostic, which may include:
* Checking the level and condition of the transmission fluid
* Read fault codes
*Physical inspection and testing of transmission
* TCU reprogramming (if necessary)
Depending on the problem identified, repairs may include:
* Replacement of transmission fluid and filter
* Repair or replacement of electrical components
* Replacing friction discs or bands
* Replacing the hydraulic coupling
* Flushing the transmission system
* TCU software update
* Repair or replacement of mechanical transmission parts