The Lift Assembly in the center of the platform will raise the axle of the truck. Once the lift has taken the bulk of the weight off of the wheel ends the Shakers, on both ends, move in opposite directions to allow the operator to visually check for excessive play in the king pins and tie rods. They move in opposite directions providing the most visible play by working each wheel end against the other. Special materials are used for -30° F (-34.44° C) A special low temperature oil is used to operate in such conditions and must be requested.