Steering Wheel Not Returning to Centre: Caster Angle and Causes

The steering wheel is expected to return to centre by itself when coming out of a turn. When this return weakens or the steering becomes heavy, the cause is usually in the front end.

What is the caster angle?

Caster is the tilt of the steering axis relative to the vertical when viewed from the side. Positive caster makes the steering wheel self-centre and keeps the car straight at high speed.

Why the steering wheel does not return to centre

• Reduced caster: caster can decrease after an impact or because of worn bushings.
• A binding ball joint or strut top mount: makes it harder for the steering to return.
• Low tyre pressure: makes the steering heavier and weakens the return.
• A left-right caster difference: also causes the car to pull to one side.

What to do

First check the tyre pressures, then have a front-end inspection and a 3D alignment measurement. The caster value is clearly shown in the measurement and helps identify the source of the problem.