What Causes Abnormal Noise in the Transmission?
2 Answers
Abnormal noise in the transmission is caused by: 1. Faulty friction plates inside the transmission; 2. Abnormal transmission oil pressure; 3. Excessive wear of internal mechanical components in the transmission. When bearings wear out, the gaps increase, and the precision of component fit decreases. If the bearings are damaged, they cannot operate normally, leading to abnormal noises and potentially causing further damage to transmission components, exacerbating the issue. The solution is to immediately take the vehicle to a repair shop for inspection and servicing. The transmission is a mechanism used to alter the speed and torque from the engine, capable of fixing or changing the gear ratio between the output and input shafts, also known as the gearbox.
With decades of experience in driving and auto repair, I've encountered transmission noises quite often—it's usually due to worn internal gears or bearings, producing squeaking or knocking sounds during operation. For manual transmissions, a warped clutch pressure plate or faulty release bearing can also cause noise; in automatics, it's often clogged valve body oil passages or torque converter failure. Fluid issues are another major factor: low or contaminated transmission oil leads to insufficient lubrication, increasing friction and noise. The problem becomes more noticeable at high temperatures, with rough shifting accompanied by abnormal sounds. Delaying repairs risks component failure, potentially requiring a full transmission replacement at much greater cost. My advice: don’t improvise. Note the noise type, then take it to a trusted shop for a diagnostic scan—early intervention saves both hassle and money.
