0 0 Rockwell RS21145 Rear Differential for a Rockwell RS-21-145 Newly Listed $1,000 USD Remanufactured Rockwell RS-21-145 rear, rear differential assembly. 5.57 ratio. 1 Year warranty for parts or Swap out for another unit. $500 For Labor. Towing not covered ConditionRemanufacturedRear End5.57 ratioFits To Make(s)ROCKWELLFits To Model(s)RS-21-145Stock NumberBP TRS RS-21-145/5. MLS Number14050338CategoryDifferentials, Rear Last Updated12/18/2025 LocationFitchburg, MA, US Sold ByRydemore Heavy Duty Truck Parts (888) 519-___ SHOWNUMBERCall Seller Email Seller Save More Info