What is a CV joint in a car?
2 Answers
Automotive CV joints are divided into inner CV joints and outer CV joints, also known as "constant velocity universal joints". They are crucial components in a car's drivetrain system, responsible for transmitting the engine's power from the transmission to the two front wheels, enabling the vehicle to drive at high speeds. A typical automotive CV joint consists of the following parts: bell-shaped housing, tripod bearing or steel balls, dust cover, retaining ring, and grease. The main inspection points for CV joints include: 1. Internal and external spline dimensions and thread sizes. 2. Checking the oil seal retaining dimension of the outer CV joint - this dimension usually varies among different CV joint models. 3. Verifying the correctness of the internal spline's circlip groove, as the width of the circlip groove affects the axial movement of the CV joint on the driveshaft after installation. 4. Material and heat treatment properties, which require specialized equipment for inspection.
I've been running an auto repair shop for many years, and CV joints are quite common in car chassis. They're essentially constant velocity joints that allow the drive shaft to change angles freely when the wheels turn while smoothly transmitting power without causing the steering wheel to vibrate wildly. Especially in older cars or vehicles frequently driven on mountain roads, CV joints are prone to wear. If the boot tears and lets in sand or gravel, they start making clunking noises, and the steering may shake. In severe cases, the axle can even break down completely. I recommend checking the boot and seal every 10,000 kilometers, and replenishing with fresh grease if there's leakage - it's a low-cost maintenance item. If it's truly damaged, replacing the part may cost a few hundred dollars, but safety comes first. Neglecting it could affect the braking system and significantly increase accident risks. The key to daily maintenance is regularly checking the seal integrity and paying attention to any abnormal noises.
