When a wheel alignment is done on a car with front torsion bars, what should be checked and adjusted first?

When performing a wheel alignment on a car equipped with front torsion bars, it is critical to first check and adjust the curb height. This is because the curb height establishes the vehicle’s ride height which directly influences the angles that are measured and adjusted later in the alignment process, such as camber and caster angles.

By ensuring the curb height is correctly set, you create a stable baseline from which all other alignment angles can be accurately measured and adjusted. Torsion bar suspension systems may have adjustments in the bars themselves that can affect the overall height of the vehicle, and addressing this first helps ensure that the vehicle has the appropriate stance. When the ride height is not set correctly, it can lead to inaccurate alignment, potentially causing uneven tire wear or other handling issues.

Adjustments to caster angle, toe setting, and checking wheel bearings can then follow, as these settings are influenced by the vehicle's curb height. Therefore, starting with curb height ensures all subsequent adjustments are performed accurately.