Abstract: A differential wheel bearing adjustment tool is provided for use with wheel differential bearings having threaded bearing cups. The tool includes a pair of plates that engage the outboard ends of bearing cups in sets of bearings rotatably supporting the plain half and flanged half of a differential case within a differential carrier. A threaded rod extends between and through the two plates and nuts are disposed on the rod on sides of the plates opposite the bearing cups. Rotation of the one or both of the plates causes a corresponding adjustment in the position of the bearings thereby resulting in positional adjustment of the bearings.