In the overall scheme of things, control-arm bushings may seem like a relatively unimportant part of a vintage Chevy musclecar.
In reality, these simple rubber pieces serve two critical purposes. First, the control arms-and thus the vehicle's suspension-pivot on these bushings. And along with the bolts or cross-shafts that run through them, they secure said vehicle's suspension to its frame. But after decades of service, the GM-spec rubber control-arm bushings are often in sorry shape. With this in mind, we set out to replace the original rubber bushings in a typical set of front A-arms with a set of high-performance polyurethane bushings from Energy Suspension.
Even when new, the hole in the center of these rubber donuts-used for their cushioning properties, not their performance qualities-will deflect under load. According to Energy's Billy Harrill, they actually deform with age and exposure to the elements. When this happens, the suspension pivot points get sloppy, and the control arms move in ways the factory never meant them to.
At the very least, rehabbing worn-out original bushings will restore a vehicle's factory handling capabilities. Polyurethane bushings, however, are created to allow less deflection than rubber bushings without creating an unduly harsh ride. So the suspension is provided with a more precise pivot point that changes less under load, leading to improved handling.
A machine shop can easily press out bushings and install the new pieces. On the other hand, as our man Harrill showed us, much of the swap can be done at home, given patience and the right tools. As you decide which is which, remember this: Given what's riding on these bushings, this is a job you want to get right.