There are several parts responsible for transferring the power from your engine to the drive wheels on the car. The components in this system are referred to as the driveline, and it often includes the transmission, the driveshaft, the differentials, and the axles. Damage to any one of these parts can disable the vehicle, but there are some common issues that come up, and most are not difficult to fix.
If you notice vibrations coming from under your vehicle as you drive, you may have a problem in the driveline that needs some attention. Vibrations can come from bearings or joints in the system wearing until they become loose and allow components to produce vibrations.
Often the vibrations will start small and increase as the part causing the problem continues to wear. A worn bearing will eventually freeze up if it is not replaced, and a joint in the system could break, so take your vehicle to a driveline repair shop for assessment as soon as you notice the vibration or if it gets worse.
Most vehicles have axle bearings that support the drive axles, carrier bearings in the differential, universal joints in the driveshafts, and seals throughout the driveline. A repair tech should check these components if you notice a change in how the vehicle feels going down the road.
The universal joints in your driveline are made up of four bearing assemblies and four seals. They allow the driveshaft to move with the suspension as you drive, but one of the bearings is faulty, the entire U-joint will begin to wobble as the driveshaft spins.
Eventually, the vibration will increase, and if you do not have a driveline repair service replace the joint, it can eventually come apart, causing the driveline to come loose from the transmission or the rear differential. A failure of the driveshaft can cause other parts to be damaged when the U-joints fail, so take the vehicle to a shop as soon as you notice a problem.
If the U-joints are causing the vibration, you may also notice a banging noise when you shift the vehicle into gear, most notably on cars or trucks with automatic transmissions. You will often feel the vehicle jump simultaneously because the universal joint is moving around in the mount.
Most driveline repairs services can remove the driveshaft, replace the U-joints on both ends, and reinstall the driveshaft quickly, and the cost associated with the repair is not very high. If you neglect the repair, a failure somewhere in the system could do a lot of damage and add to the cost of repairing the vehicle substantially.