; HomeHeavy Duty Truck PartsDifferentials & Differential PartsAxle Housings (Rear)Meritor/RockwellRS21-145Used ROCKWELL RS21-145 Axle Housing (Rear) Used ROCKWELL RS21-145 Axle Housing (Rear) Unfortunately this part is temporarily unavailable. View other Meritor/Rockwell RS21-145 Axle Housings (Rear)