A
radius rod (also called a
radius arm or a
torque arm) is a
suspension link intended to control
wheel motion in the longitudinal (fore-aft) direction. The link is connected (with a
rubber or solid
bushing) on one end to the wheel carrier or
axle, on the other to the
chassis or
unibody of the vehicle. Radius rods are also sometimes used in aircraft with fixed (non retractable) undercarriages.