What’s better—polyurethane or rubber bushings?

Question:

I’m starting a body-off-the-chassis full restoration of a 1970 Chevelle and wonder if you could provide me with some input related to the subject.

I’ve played around with hot rods in the past but got out of it for over 30 years so I’m a little behind the eight ball. My question is simple; I need a complete set of bushings for this car. What really is the best type of bushing, polygraphite or original rubber?

Thank you for your assistance and I do appreciate your monthly magazine. I subscribed about two years ago in preparation for my upcoming retirement project!

Answer:

I really can’t proclaim that rubber or polyurethane bushings are better. Each has its own particular benefits and its own disadvantages and which is better for you depends on various factors, including how you will use your car, what your budget is, and what type of restoration you are going to do.

Polyurethane bushings are considerably more rigid than rubber bushings. The added rigidity translates to a noticeably stiffer suspension and more precise steering behavior. The reduced compliance of the polyurethane bushings means that wheel alignment and suspension geometry don’t deviate as much when the suspension and steering are subjected to very heavy loads during competitive or aggressive driving maneuvers. So, if you plan to drive your Chevelle competitively or very aggressively then you will enjoy the benefits of polyurethane bushings.

There are some negatives to using polyurethane bushings, however, and you should be aware of these before making your decision.

Polyurethane bushings typically cost two or three times as much as OEM rubber bushings. Poly bushings have earned a reputation for being noisy, particularly in very cold weather, and though this has been largely addressed with graphite impregnation and more sophisticated manufacturing compounds, some people still experience squeaks or other annoying noises. The same added rigidity that yields more precise handling also causes polyurethane-bushing-equipped cars to have stiffer ride characteristics. And, of course, polyurethane bushings look markedly different from OEM rubber bushings so if you’re performing a stock restoration poly bushings will look oddly out of place.