Abstract: A universal joint comprising outer and inner joint members with circumferentially spaced grooves extending lengthwise of the members; and balls disposed one in each facing pair of grooves in the joint members for torque transmission between the members; wherein at least some of the grooves in one of the joint members are each provided in a groove base portion with a recess extending lengthwise of the groove, and a spring element is disposed in each said recess and arranged to engage the respective ball to bias it radially of the joint and preferably also axially to the central region of the spring element.