Anyone who's heard or felt their driveshaft wobble as they are driving down the road knows that what they are experiencing is not normal - and that most likely their driveshaft center support bearing has failed. This can be easily felt accelerating between 2,000 and 5,000 RPMs, or for a few seconds after taking your foot off the gas. Without a doubt, this cannot go unaddressed. Sure, there are a lot of rubber bushings and dampers that will absorb excessive vibrations. But this is not just excessive - it is dangerous. Your rear differential ring and pinion gears are being eaten up with all that vibration, and all of your other drivetrain components will be adversely affected too. No one wants to be looking at the repair bill to fix or replace their driveshaft center support bearing, but it would be a much more expensive bill if it also included your rear axles and differential as well. And that's if you are lucky enough to get your car or truck in for repair before something bad happens. The worst case scenario is a complete loss of drive capabilities from your rear wheels and your car is stranded.
The earliest cars had front-engine and rear-wheel drive layouts. Part of this design is the challenge of transferring the torque from the transmission to the rear wheels. This is done by employing a system of propeller drive shafts, a differential that contains a ring and pinion gear, and axles that spin the wheels. The drive shaft runs the length of the car; and as this driveshaft spins and as the car encounters obstacles, the driveshaft center support bearing keeps it in place. It is a large horseshoe-shaped bracket that bolts to the floor pan that includes a roller bearing surrounded by a rubber membrane. This ensures that the bumps in the road and vibrations coming from the engine and transmission are absorbed so the driver and passengers are not shaken and vibrated to the point of sickness.
While your driveshaft center support bearing is a relatively simple part, installing it can take a while. Here are the steps: