What Are the Causes of Transmission Noise?

[DiIsla]

The causes of transmission noise include: 1. The oil pump produces noise due to excessive wear or improper hydraulic oil level (too low or too high); 2. The torque converter generates noise due to damage to the lock-up clutch, guide wheel one-way overrunning clutch, etc.; 3. Noise from the planetary gear mechanism; 4. Noise from shift execution components. For fault diagnosis and troubleshooting, check the hydraulic oil level of the automatic transmission. If it is too high or too low, adjust it to the normal level. Use a lift to raise the vehicle, start the engine, and check the location and timing of the noise in the automatic transmission under neutral, forward, and reverse gears. If there is continuous noise in the automatic transmission in any gear, it is usually caused by the oil pump or torque converter. In this case, disassemble the automatic transmission for inspection, check whether the oil pump is worn, and whether there is a large amount of friction powder in the torque converter. If abnormalities are found, replace the oil pump or torque converter. If the automatic transmission only produces noise while driving and is silent in neutral, it is likely due to noise from the planetary gear mechanism. In this case, disassemble the automatic transmission and inspect each component of the planetary gear set for signs of wear, check for broken gears, wear or sticking of the one-way overrunning clutch, and damage to bearings or thrust washers.