What will trailing arms, a panhard rod, and a torque arm do for me?
Trailing arms will keep the rear straight, relative to the body, in the forward/aft direction. When you accelerate, they push the car forward. When you brake, they pull back on the body. They allow for the up/down motion of the axle when, for example, you hit a bump. The panhard rod (probably called a “track bar” in the service manual) locates the rear axle, relative to the body, in the lateral, side-to-side direction. When you go around a turn, the centrifugal force generated on the body is transmitted to the rear end (which hopefully is sticking to the ground) via the panhard rod. The torque arm locates the rear axle, relative to the body, rotationally. When you accelerate or brake, a torque moment is generated around the axle. The torque arm prevents the rear axle from rotating, and transmits the torque to the body of the car. So when you accelerate, the torque arm is pushing up on the body of the car. A number of companies produce aftermarkets pieces which prvoide even better handl