Control Arm
What it is
A control arm connects the wheel hub/knuckle to the chassis and lets the suspension move up and down while holding the wheel in alignment. Its bushings and ball joint are common wear points.
What it does
It locates the wheel and absorbs road inputs through its bushings. Worn bushings or a loose ball joint cause clunking, vibration, uneven tyre wear and wandering steering.
Symptoms of failure
- Clunking or knocking over bumps
- Vibration or wandering steering
- Uneven or rapid tyre wear
- Steering that pulls or feels loose
- Visible cracked bushings or play in the ball joint
Which vehicles need it
Every car. Potholes and rough roads wear the bushings and ball joints faster.
Replacement cost
| DIY (part only) | $60–$250 |
|---|---|
| At a shop (parts + labor) | $250–$600 |
| Replacement interval | No set interval — replace on worn bushings or ball joint; align afterwards. |
| DIY difficulty | Moderate–Hard (DIY) — pressing bushings and a wheel alignment are usually needed |
| Recommended brands | MOOG, TRW, Delphi, Mevotech |
Where to buy the part
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Recommended products
Tools to diagnose it
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Frequently asked questions
What does a bad control arm sound like?
Usually a clunk or knock over bumps and during braking or cornering, from worn bushings or a loose ball joint. You may also feel vibration or vague steering.
Do I need an alignment after replacing a control arm?
Yes. Replacing a control arm changes the suspension geometry, so a wheel alignment afterwards is needed to avoid pulling and premature tyre wear.