What Causes the Clicking Sound in the Differential?
3 Answers
Differential clicking sounds are generally caused by low machining precision of the gear teeth or improper meshing. In such cases, it is best for the car owner to have the vehicle inspected and repaired at a 4S shop. Below is relevant information about automotive differentials: Principle: The differential is a device designed to adjust the speed difference between the left and right wheels. In four-wheel drive systems, to power all four wheels, they must be interconnected. If all four wheels are mechanically linked together, the car cannot rotate at the same speed when cornering. To ensure the car's rotational speed remains consistent during curves, a center differential is added to adjust the speed difference between the front and rear wheels. Function: The automotive differential primarily eliminates mechanical interference caused by inconsistent rotational speeds of the left and right wheels during turns. Without a differential, mechanical damage could occur due to the speed discrepancy between the wheels. For example, conventional human-powered tricycles do not have differential devices installed, so they can only use single-side drive when turning.
I was also quite puzzled when I encountered this situation before. Later, after consulting an experienced mechanic, I learned that differential noise is mostly caused by internal gear issues. Especially for older cars that have been driven for over ten years, the wear on the planetary gears and axle gears leads to increased clearance, causing creaking sounds when turning. If the bearings are damaged, there will also be metallic clanging noises, sounding like someone is hammering the chassis. Last time, after driving my car on mountain roads in the rain, it started making noise. Upon disassembly, I found the differential oil had turned into chocolate paste, leading to dry grinding of the gears due to insufficient lubrication. Another easily overlooked point is the driveshaft universal joint—when that wears out, it can make the differential "dance" along with it. I recommend getting it checked at a repair shop as soon as possible. Don’t wait until the gears are shattered to take action.
I noticed the differential noise during a long-distance drive—it made a clicking sound every time I took a turn. The mechanic said there are three common causes: gear wear, bearing failure, or fluid issues. The most typical sign of gear wear is pronounced noise during turns, as that's when the differential is under the most load. If it's a bearing problem, the noise occurs whether you're driving straight or turning, sounding like crumpling a plastic bag. They used a stethoscope to inspect my car and found shattered steel balls in the left-side bearing. Also, differential fluid should be changed on time, or metal debris will accelerate wear. I remember that repair cost me over 800 yuan, including a replacement of specialized gear oil.
