Mercedes-Benz W203: front end rattle and creak over bumps
What usually causes a W203 front end rattle over bumps?
The most common causes are the anti-roll bar's body bushes and the bar's connecting rods, also called drop links, which wear and loosen. Next, check the lower control arm rubber bushes, which can tear and cause a hard knock over bumps.
How is the cause of a front end rattle found?
Lift the car and shake the drop links and the wheels, and the play becomes visible. Cracks in the control arm bush show when it is levered sideways. Also check the strut top mount rubbers and nut, and the lower ball joint. A broken control arm ball may only show up in an inspection on a lift.
What else can cause creaking or bangs at the front?
The anti-roll bar body bushes can creak when turning, and loosening and lubricating them has removed the creak. If there is a bang when the steering wheel is turned, the cause can be a seized strut top bearing. A rattle can also come from a failed centring of the aluminium control arm. Suspension work is safety-critical, so have a workshop check the result.