1990 Meritor/Rockwell RT40-145, Truck Tractor, Rear Rears (Tandem Rear or Single), Fits to: Peterbilt 379, (Used) 1990 Peterbilt 379, COMPLETE REAR DIFFERENTIAL GEARS ONLY- Make: Meritor, Model: RT40-145, Ratio: 3.58, Capacity: 19,000 Lbs, For more information about this item, give us a call. We ship Worldwide! (CRG HEAVY TRUCK PARTS) 929 W PULASKI HWY ELKTON, MD 21921, Ratio 3.58, Serial# TBD, Truck Year 1990 1XP5DB9X8LN282500