BMW E46 Lower Control Arm Bushings: Play and Replacement
How do you know the E46 lower control arm rear bushings are worn?
Typical symptoms are knocking when driving over a bump, steering wheel vibration when braking and the car wandering. The play is not always found at the annual inspection, but wide low-profile tyres can reveal it. After replacement the vibrations and rattles usually stop.
How do you check the lower control arm rear bushing for play?
By prying the end of the control arm with a bar. If the end moves more than 5–10 mm, the bushing must be replaced. Check the ball joints and the tie rod ends at the same time, as the knocking can come from them too. If the ball joints are broken, the whole control arm is replaced.
Must the bushings be replaced on both sides, and what is done after the replacement?
Always replace the bushings and the mounts in pairs: a worn bushing flexes more than a new one, and the wheel angles become asymmetric. The size of the rearmost bushing is 66 mm. After the replacement the wheel alignment must be adjusted, otherwise the steering wheel stays crooked.