4 0 Rockwell SUDD Rear Differential $1,100 USD Good used Rockwell SUDD rear, rear differential assembly. 6.38 ratio. 90 day guarantee for swap or refund ConditionUsedRear End6.38 ratioFits To Make(s)ROCKWELLFits To Model(s)SUDDStock NumberRyd SUDD/6.38/46 MLS Number13426327CategoryDifferentials, Rear Last Updated7/30/2025 LocationFitchburg, MA, US Sold ByRydemore Heavy Duty Truck Parts (888) 519-___ SHOWNUMBERCall Seller Email Seller Save More Info