1978 Other Other, Truck Trailer, Steering Gears, Fits to: Mack RD685S, (Used) 1978 Mack RD685S, STEERING BOX- Make: Hydrapower, Model: M, Material: Steel, Location: Inside Frame, For more information about this item, give us a call. We ship Worldwide! (CRG HEAVY TRUCK PARTS) 929 W PULASKI HWY ELKTON MD, 21921, Truck Year 1978, VIN RD685S3685, Serial# TBD RD685S3685