A tool for removing and installing serpentine belts in vehicles has a drive bar, a double box end wrench and a socket. The drive bar has a handle at a first end and a fitting at an opposite second end that is used to connect to the double box end wrench. The double box end wrench has a first end defining a polygonally shaped opening and an opposite second end that defines a ratcheting wrench having a first plurality of teeth on an inner circumference thereof. The socket defines a second plurality of teeth on an outer circumference thereof that are adapted to be received by the ratcheting wrench first plurality of teeth. The socket also defines one of a polygonally shaped opening and a polygonally shaped tang that is received by a work piece of an vehicle idler pulley.