Replacing damaged shock absorbers: Used to safely compress the old spring until its length is reduced, allowing it to be disassembled and removed from the car and replaced with a new one. Replacing strut mounts: When the rubber parts or upper bearings of the shock absorber need to be replaced, the spring must first be compressed to safely loosen the central nut without the spring suddenly recoiling. Adjusting vehicle height (lowering or raising): Used when the car owner wants to install short sports springs or add extensions to raise the car. Performing general suspension system maintenance: Facilitates access to the parts surrounding the suspension system that the spring may obstruct when disassembled in its normal tensioned state.