View 4 Photos View 0 Videos Meritor-Rockwell QR 100PX Rear Differential for a 1989 Gradall G-660C Contact for price (Used) Gradall G-660C, TANDEM CUTOFF- Make: Rockwell International, Model: QR 100PX 7, Ratio: 780, Customer Part Number: 83683370, Serial Number: NKA88046921, Hub Bolts: 6, Brake Type: Drum,... ConditionUsedRear End7.80 ratioFits To Make(s)GradallFits To Model(s)G-660CWill Fit Year(s)1989Part Number83683370Stock NumberP-37284 MLS Number11820991CategoryDifferentials, Rear Last Updated3/12/2026 LocationElkton, MD, US Sold ByCRG Heavy Truck Parts (844) 402-___ SHOWNUMBERCall Seller Email Seller Save More Info