Damping coefficient of my car?

I was wondering how I can estimate the damping coefficient of my car by doing the hand bouncing the car body and watching the motion of the car?

Mechanics usually bounce the car by applying hand force and watching how the car moves in harmonic motion. Is there a way to estimate the damping coefficient by using this technique?

I was thinking Mythbusters type stuff like camera, but I have an IPHONE 4 if I know the FPS of the camera I might be able to measure it frame by frame, if I have a measurement stick and reference point. Not sure if there's a practical way of doing this, I know the motion will be simple harmonic damped motion, so if you count the half-cycles maybe you can get the damping, not sure of the forumula to use?

Or is there another technique like dropping the car a few inches or something to estimate it?

Actually, bouncing a car and counting the number of "cycles" until it stops bouncing is a measure of the quality of the shock absorbers. Good shocks in a car will stop the bounce within 3-4 bounces, while worn out shocks will allow it to bounce longer before stopping.

Shock absorbers ARE damping devices, Ivy. They restrict the compression and release accelerations of the springs and this dampens the harmonic motion.
You couldn't know the coefficient of damping unless you knew the undampened condition.

If you wanted to compare the oscillation of the car with the damper removed to the oscillations when the damper was in place, then you COULD do it. But you would need precise measurements of the amplitude and time do it. You could approximate it, though.