If you’ve been taking your truck on a lot of off-road adventures then you know how important it is to have reliable suspension. The Twin-Traction Beam axle on the models uses a pair of rubber bushings to soften the connection between the axle and the frame. These help to dampen some of the noise and vibration that can travel from the road (or off-road) to the cab, but hard use and time hollow these bushings out. This can cause “clunking” noises under your Bronco or a steering wobble after hitting a bump. Replacing the stock rubber bushings with polyurethane pivot bushings will eliminate those problems and last a lot longer than rubber.
Off-roading or even regular driving on poorly maintained roads are not the only conditions that will cause rubber bushings to fail, and lets face it, you don’t have a 4WD Bronco to cruise down a glass smooth interstate. You want to crawl over rocks or see how deep that mud hole really is. Motor oil, road grime, salts, and heat will all begin to take their toll on rubber, but pivot bushings will brush off the elements that will eventually destroy rubber. A little more vibration for a sturdy axle-to-frame connection is not a bad trade.