What Causes the Clicking Sound in the Transmission When Braking in an Automatic Car?
2 Answers
Automatic transmission clicking sound when braking can be caused by: 1. Loose transmission housing bolts; 2. Excessive play between the gearshift lever and the shift fork groove; 3. Worn or damaged bearings; 4. Long overdue transmission fluid change; 5. Gear tooth surface metal peeling, tooth breakage, or misalignment during assembly; 6. Gear meshing clearance issues; 7. Use of low-quality automatic transmission fluid; 8. Water ingress into the transmission without timely repair. Common automatic transmission gear positions include: 1. R (Reverse) gear, which should only be engaged after the vehicle comes to a complete stop to avoid transmission damage; 2. N (Neutral) gear, allowing the vehicle to coast when engaged.
I encountered the same issue with a friend's car last time. The transmission makes a particularly noticeable rattling sound when braking. It's mainly due to a problem with the torque converter in the transmission; the blades shake and collide when the oil pressure is unstable. It could also be the sound from the shift solenoid valve—when braking, it adjusts the oil circuit, producing a metal clanking sound. Aging transmission mounts can cause this too; when the rubber cracks, metal directly rubs against metal, especially noticeable when parking. Lastly, don’t overlook the transmission fluid—if it’s too dirty or too low, it can cause gears to operate poorly and produce abnormal noises. Get it checked soon; delaying could turn this into a major repair.
