What is the difference between a torsion bar and torque arm on a semi truck?

A torsion bar is a type of suspension component that uses the twisting of a bar to absorb shocks and support the vehicle's weight, providing stability and ride comfort. In contrast, a torque arm is a structural element that connects the axle to the chassis, helping to manage the torque generated during acceleration and braking, which prevents axle rotation. While both contribute to the vehicle's handling and stability, the torsion bar primarily focuses on suspension, while the torque arm focuses on torque management.