The brief
The E200 was clunking from the front over potholes and bumps, drifted to one side without correction on a flat road, and an underbody check showed visible bushing damage across the control arms. Three converging signs of a worn front-suspension set.
The front suspension on this car uses several aluminium arms per side to locate each wheel, each one carrying rubber bushings and a ball joint. When those wear, the wheel can shift a fraction under load: the slack gives the clunk over bumps, and the geometry drifting off is what makes the car wander to one side on a straight road.
The diagnosis
Underbody inspection found cracked bushings on both upper control arms and matching wear on both lower arms, with measurable ball-joint play. The drift was simply the misalignment that all that slack had let creep in.
Replacing the worst few and leaving the rest would have meant a return visit, and on a multilink front end the labour to get in there is much the same whichever way you do it. So the right scope was a full set of new arms across both sides, then a fresh four-wheel alignment to reset the geometry on the new parts.
The work
The car was lifted, the ball joints disconnected from the knuckles, and both upper control arms and both lower arms dropped on both sides. New Mercedes-spec arms went on with fresh bushings and ball joints, the chassis bolts torqued to spec with the suspension at ride height so the bushes settle in their neutral position.
Then the car rolled onto the alignment rack for a full four-wheel alignment, camber, caster and toe brought back to factory, with the before-and-after numbers printed for the owner.
The outcome
No clunking over bumps, the car tracking straight without correction, and the steering feel sharp again.
The E200 went home with the front suspension reset. For the owner that is a car that feels precise and planted instead of loose and wandering, plus, with the geometry back in spec, front tyres that will wear evenly rather than being scrubbed by a misaligned front end.
