How to Calculate Unsprung Weight

Unsprung weight is the measure of a vehicle's total weight that is not supported by the vehicle's suspension system. Unsprung weight includes the weight of the wheel, hub, brakes as well as the A-arm and I-beam assembly. Calculating unsprung weight is important because reducing the unsprung weight can lead to improved handling characteristics on any vehicle. Fortunately, the process for calculating unsprung weight does not require the use of any complicated mathematical formulas.

Things You'll Need

  • Lift
  • Floor jack
  • Commercial scale
  • Load the vehicle on a lift or floor jack so the vehicle's weight is not supported by the suspension. This can be accomplished by supporting the vehicle by its frame and not by the wheels.

  • Remove the shock and springs from the vehicle as well as any swaybars that may be installed.

  • Place a scale under each of the vehicle's tires and record the weight.