Крис Младенов Audi A4 and A6 Suspension Knocking: Worn Control Arms You drive over a speed bump or down a rough road and hear a sharp little "knock-knock" from the front. If you own an Audi A4 or A6, you'll probably know exactly what I mean. Audi A4 and A6 suspension ... Audi A4 Audi A6 Control arms Suspension Wheel alignment Dec 23, 2023