Possible causes of impacts when shifting gears in an Aisin automatic transmission:
Mechanical problems:
* Wear of clutches and steel discs
* Malfunction of pistons, cylinders or solenoids
*Transmission fluid leak
*Damage to planetary gear or clutch drum
Electrical problems:
* Faulty solenoids or wiring harness
*Transmission control module (TCM) malfunction
Hydraulic problems:
* Clogged or dirty hydraulic filter
* Fluid leak from hydraulic pump
* Pressure regulator malfunction
Software problems:
* Bugs in TCM software
* Outdated software
Other possible reasons:
* Worn or contaminated transmission fluid
* Incorrect transmission fluid level
* Wear of transmission rubber mounts
* Problems with driveshaft or transfer case
Diagnosis and troubleshooting:
1. Check the level and condition of the transmission fluid.
2. Inspect the transmission for leaks or damage.
3. Use the diagnostic scanner to read the trouble codes.
4. Check solenoids, wiring harness and TCM for faults.
5. Check the hydraulic filter and pump for blockages or leaks.
6. Update TCM software if necessary.
7. Take the vehicle to an authorized service center for further diagnostics and repairs.
Note: Shock when shifting gears can cause further damage to the transmission, so it is important to promptly identify and correct the cause.