Abstract: A spring compressor tool is disclosed for use on, for example, the independent suspension assembly of a vehicle, without the necessity of removing the suspension from the vehicle. The tool includes upper and lower U-shaped pressure shoes having helical-shaped outer peripheries for receiving spaced coils of the spring intermediate the opposed connected ends of the spring. A pair of pneumatic cylinders are positioned between the upper and lower shoes. Cylinder rods extend within the cylinders and mount pistons at one end. A header assembly includes pressurizing and venting valves and the cylinder rods define air passageways which communicate with the header assembly and with the cylinders. Return springs are provided adjacent the rods to urge the shoes to a non-compressed position. Air pressure is provided through the passageways to move the shoes toward one another to compress the suspension assembly spring.