Abstract: A protective cover assembly for universal joints which is particularly suited for commercial vehicles such as trucks and buses, as well as off-road vehicles, comprises forward, intermediate and rearward shields that overlie but do not touch respective universal joints. In one embodiment, the shields have outside brackets that attach to either the cover of a transmission or the cover of a differential gear mechanism and are adjustable inward and outward relative to the covers. In another embodiment, the shields have brackets that respectively have straps for connecting to the body underside frame rails of the vehicle and are adjustable forward and rearward to cover the universal joints the shields overlie.