The coil springs on a car are part of the suspension. They are designed to spring up and down as the car travels across the road surface. If these springs weren’t in place the car would not allow for movement and therefore would break apart.

If replacing coil springs you are often advised to do them in pairs – i.e both on front axle or both on the rear –this is not just because the garage want to charge you more money. Often the springs that you can buy cheaper are slightly different for the manufacturer’s standard and therefore you need to have two of them so the car sits balanced on both sides. You may choose to buy a slightly more expensive spring and only fit the one, but if the springs have previously been changed and you were not aware of it you may not be able to fit the new one you have purchased. Prices for changing springs can vary on garage and the model of the car but if you are prepared to source the parts yourself you may find that you can nearly half the price quoted.