What Causes Abnormal Noises Outside the Car When Shifting an Automatic Transmission?
2 Answers
Abnormal noises during shifting in an automatic transmission can be caused by the following reasons: 1. Large valve clearance when the engine is cold. Poor lubrication leads to noise when shifting from cold to warm engine conditions, lasting about 3 minutes, but this is normal. 2. Issues caused by parking on a slope. If you engage the P gear first and then pull the handbrake when parking on a slope, the car's weight will be entirely on the P gear due to inertia, causing noise when shifting. If you pull the handbrake first, the handbrake bears the weight, and no noise will occur. 3. Transmission problems. Wear in the transmission, loose drive shaft, differential wear, worn output shaft inside the transmission, worn transmission gears, or faulty shifting mechanism. It is essential to visit a 4S shop or a professional auto repair shop promptly for technician repairs.
As a frequent driver, I've noticed that unusual noises outside the car during automatic transmission shifts are mostly caused by issues in the drivetrain or chassis components. For example, worn transmission gears, loose differentials, or loosened exhaust pipe mounting bolts can produce noises during shift vibrations. External noises may also come from aging suspension systems, such as damaged shock absorbers causing creaking sounds. Never ignore such situations, as delaying repairs may lead to part failures or even driving hazards. I usually check for obvious looseness under the car, and if that doesn't help, I take it to a repair shop. Regular transmission fluid changes and chassis maintenance can effectively prevent these noises, making driving more reassuring.