What is the purpose of using shockers in a car?

Answer 1

A so-called shock absorber in a car does not in fact do much to absorb shocks - try running over a speed bar and you'll soon find out.

The shock absorber in fact does its most useful work by damping out the oscillations that would otherwise persist in the springs after crossing a bump.

And this is the simple test as to whether the shocks are still working - just bounce the car down on its springs, and see how many bounces occur before the motion stops. It should certainly stop bouncing before three oscillations.

These unwanted oscillations would otherwise interfere with the wheel balance and steering, and certainly do affect the braking effort.