What Causes Transmission Noise?
2 Answers
Noise may occur due to incomplete clutch disengagement. For manual transmissions, the first possible cause of noise is incomplete clutch disengagement. The second possibility is the presence of gear debris, where fragments between gears continuously collide, or it could be damaged gears. More detailed information is as follows: 1. For automatic transmissions, the issue might lie with the gear set, requiring prompt repair. Automatic transmission fluid should generally be replaced every 2 years or 40,000 kilometers. Manual transmissions, however, require maintenance every 3 years or 60,000 kilometers. For a repaired transmission, it is strongly recommended to perform the first service at 3,000 kilometers, followed by replacement every year or 20,000 kilometers thereafter. 2. Transmission fluid operating under high temperature and pressure can accumulate sludge and impurities, causing the fluid to thicken and lose its fluidity. This reduces the protective layer between components, leading to direct friction and increased mechanical wear, which results in noise. If the noise is rhythmic, try accelerating. If the noise intensifies, it is likely due to gear surface peeling or broken teeth, or possibly incorrect installation during repair, and should be inspected promptly. 3. If noise occurs in neutral but disappears when the clutch pedal is pressed, it is usually due to wear or looseness in the front and rear bearings of the transmission's input shaft, or noise from the constant mesh gears. If noise persists in all gears, it may be due to the rear bearing of the output shaft. Severely worn or damaged bearings should be repaired or replaced. If irregular noise occurs at low speeds, assess the noise level. Loud noise may indicate poor gear meshing inside the transmission, necessitating removal and inspection.
I've encountered transmission noise issues several times, mainly caused by mechanical component wear or damage. For example, worn gears can produce clicking sounds during high-speed operation; bad bearings are also common, where increased friction creates noise. Insufficient or contaminated fluid is another factor - inadequate lubrication makes the transmission groan. Synchronizer problems are noticeable during gear shifts with abnormal sounds. Clutch failures may also cause abnormal noises while driving. I've found regular maintenance crucial - any noise should prompt immediate inspection to prevent total transmission damage. I recommend starting with simple checks like fluid level and oil changes first, then proceed to professional repairs if needed.
