Rear-wheel drive vehicles often use a driveshaft to connect the transmission to the rear differential to transfer power from the drivetrain to the drive wheels. The driveshaft has several universal joints in it that can wear, and some symptoms can let you know that it is time for a driveshaft repair or service.
Driveshaft Noise
When you put your car in gear, apply the gas pedal, and hear a clucking sound, it is often the universal joints in the driveshaft moving because the bearings are worn, and the joints need replacing. Each joint in the driveshaft has a fitting to add grease under the bearing caps when your car goes in for service.
If the service is not done regularly, the bearings can dry out, and the grease will burn up, allowing movement in the joint that you hear and feel when torque is applied to the driveshaft. The only option when the joints dry out and make noise is to take the car in for driveshaft repair.
Replacing the u-joints is not hard, but you need the right tools for the job and knowledge of what needs replacing. The driveshaft must be correctly aligned and clocked during reassembly to ensure it works correctly. With your foot on the brake and the engine running, put the car in drive, then shift back to reverse. If you hear a loud clunking sound when shifting into both gears, you should have the driveshaft inspected and the universal joints replaced.
Vibrations When Moving
Vibrations can be caused by many different parts in your vehicle. However, if you notice a vibration that changes with the vehicle speed, check the driveshaft, axles, or tires and wheels. The best way to find the vibration is to take the car to a driveshaft repair shop or automotive garage and have the technician check everything in the drivetrain.
A dent in the driveshaft from an impact with debris on the road or something under the vehicle can cause it to wobble, producing a vibration that worsens the faster you drive. In some situations, the dent can be very small, but the balance of the system is so critical that it is enough to cause a vibration that eventually causes damage to the u-joints, the transmission output shaft, and the differential pinion shaft bearings, amplifying the problem.
Damage to the driveshaft that throws off the balance of the assembly often means the driveshaft repair shop will need to replace the shaft with a new unit and may need to consider changing the bearing and sales in the transmission and differential.
Contact an auto shop that offers driveshaft repairs to learn more.
