Buy 2012 Audi S4 Suspension Control Arm (Rear, Upper). A4, S4; Rear; Left. A5, S5; REAR; Left Arms, Wear, Sometimes - OEM Audi Part # 8K0407509N (8K0-407-509-N, 8K0407509A)

Arm. Control.
From 08/13/2012. Incl.Ball Joint & Bushings. Suspension component that connects and provides pivotal movement of the Steering Knuckle to the vehicle. Cntl. Link. Suspension.

Suspension Control Arm

Fits A4, A5, Q5, RS5, S4, S5, SQ5

A4, S4; Rear; Left. A5, S5; REAR; Left. CONVERTIBLE,. Coupe,. FROM 11/2009. RS 5; Left. SQ5; Rear; Left. TO 10/2009.
Suspension Control Arm - Repair or Replace
Control arms often don’t fail on their own, although their associated bushings can break or wear causing a clunk noise when your 2012 Audi S4 goes over bumps or changes speed rapidly—whether braking or under hard acceleration. Control arms can also sometimes become bent, causing your vehicle to pull to the left or right.