1993-2002 GM F-Body Rear Lower Trailing Arms with Rubber Bushings and Bearings Part Number: TBC-14

Description

Firebird Rear Suspension Flaws:

The Firebird rear suspension from 1982 through 2002 needs a little help with locating the differential under the chassis. The panhard rod does somewhat of a decent job laterally but what about fore and aft?

The bushings in the lower control arms are basically the problem. If you look at the lower control arm bushing you will notice air gaps on each side of the center bolt hole. The air gaps allow the differential to move fore and aft and also shift during cornering. The panhard rod has nothing to do with this movement. As a result, when you accelerate out of the corner, the rear end actually shifts and points out of the turn. This helps the car oversteer. Something we don’t really want.

Global West Advantage: Problem Solved with Rubber Bushings

The solution the Global West Suspension (Quiet Ride) rear lower control arm for the Firebird (model years—1982, 1983, 1984, 1985, 1986, 1987, 1988, 1989, 1990, 1991, 1992). The arm is designed with a spherical bearing on one end and a rubber bushing on the other end. There are no holes in the rubber bushing.

We deliberately designed the arm to use rubber because the bushing acts as a noise insulator for the street, yet we still have the control for high performance driving including racing because the bearing and the tubular arm don’t deflect. The differential does not move fore and aft nor does it shift creating oversteer during hard cornering. It is the perfect solution for the enthusiast on the street and occasional trip to race track.

For straight line acceleration the rubber bushings can generate an oscillation leading to reduced traction. Aftermarket polyurethane control arms solve some of the problem and create others. The polyurethane does not allow the differential to pitch as it needs to around corners and over bumps. The result is oversteer and a stiffer ride over bumps. Straight line acceleration is better because we have removed the air gaps in the rubber.

Replacement rubber bushings are available without the holes, and an improvement over the stock setup is achieved. However, there still is a problem. The rubber increases resistance as the suspension moves through its intended path, thus changing the spring rate, and we still have some deflection through the control arm and bushing. Some people box the lower trailing arm to gain handling; however, boxing the control arm increase the resistance during cornering and affects the rate the car sees. This leads to oversteer.