Possible causes of knocking noise when switching automatic transmission:
Mechanical faults:
* Worn or damaged friction discs: When worn or damaged, the friction discs will slip, causing shifting shock.
* Broken or worn gears: Broken or worn gears can cause the gears to rub against each other, causing a knocking noise.
* Torque converter faults: A faulty torque converter can cause slipping or vibration, resulting in a knocking noise when shifting.
* Damage to the automatic transmission housing: Shocks can occur due to cracks or damage to the automatic transmission housing, which leads to transmission fluid leakage.
* Worn or damaged bearings: Worn or damaged bearings can cause vibration and knocking noises when the gears are engaged.
Hydraulic faults:
* Insufficient transmission fluid level: Low fluid levels can cause a loss of pressure, which causes slipping and slamming.
* Clogged or faulty oil filter: A clogged or faulty oil filter restricts fluid flow, resulting in low pressure and knocking noise.
* Faulty solenoids: Faulty solenoids cannot properly control fluid flow, causing slipping or harsh shifting.
*Transmission Fluid Leaks: Leaks can cause a loss of pressure, causing slipping and slamming.
Electronic faults:
* Faulty automatic transmission control module: The control module may be faulty, causing the shifts to be mismanaged, causing a knocking noise.
* Broken or damaged electrical wires: Damaged wiring can cause loss of communication with the control module, which also causes switching problems.
Other reasons:
* Incorrect Gear Setup: Incorrectly set up gears can result in harsh shifts and knocking noises.
*Incompatible Transmission Fluid: Using the wrong transmission fluid can result in increased friction and knocking.
* Worn engine or automatic transmission mounts: Worn engine or automatic transmission mounts can allow the powertrain to move too much, resulting in knocks.