Possible causes of clicking noises when switching automatic transmissions:
1. Low or contaminated transmission fluid:
* Insufficient fluid levels can cause a loss of fluid pressure, causing gear slipping and clicking.
* Contaminated fluid can clog transmission passages, which can also cause shifting problems.
2. Faulty solenoid:
* Solenoids control the flow of transmission fluid to the various clutch packs to change gears.
*A faulty solenoid can cause delay or shock when shifting gears.
3. Worn friction discs:
*Clutches (friction discs) wear out over time, causing slippage and vibration that can be felt as a clicking sound.
4. Worn freewheel:
* The freewheel in the torque converter can wear out, causing slipping and clicking when shifting.
5. Faulty valve body:
* The valve body controls the flow of transmission fluid.
* A faulty valve body can cause the solenoids to malfunction and cause shifting problems.
6. Faulty speed sensor:
*Speed sensors provide vehicle speed information to the transmission control unit (TCU).
* A faulty speed sensor may provide false information, resulting in incorrect gear shifting.
7. Faulty drive shaft:
* A faulty drive shaft may vibrate or vibrate at certain speeds, which may feel like a clicking sound.
8. Faulty engine or transmission mount:
* Faulty mountings can cause vibration in the engine and transmission, which can be felt as a clicking sound when shifting gears.
What to do:
* Check the transmission fluid level and condition.
* Check the solenoids using a tester or scanner.
* Check the condition of the friction discs and freewheel if transmission repairs are necessary.
* Check the valve body for leaks or malfunctions.
* Check speed sensors and wiring.
* Check and replace drive shafts if necessary.
* Check and replace engine and transmission mounts if necessary.