1970 Dodge Challenger Ring and Pinion Set Chrysler 8.75 in. Rear - w/ 489 Case Housing - Ring and Pinion Set - 3.73 Ratio - 29 Spline Pinion - 1.875 in. Diameter Pinion Bearing Journal - Rear guaranteed to replace your current 1970 Dodge Challenger Ring and Pinion Set Chrysler 8.75 in. Rear - w/ 489 Case Housing - Ring and Pinion Set - 3.73 Ratio - 29 Spline Pinion - 1.875 in. Diameter Pinion Bearing Journal - Rear. 1970 Dodge Challenger Ring and Pinion Set comes new OEM 1970 Dodge Challenger Ring and Pinion Set aftermarket new 1970 Dodge Challenger Ring and Pinion Set of remanufactured 1970 Dodge Challenger Ring and Pinion Set Chrysler 8.75 in. Rear - w/ 489 Case Housing - Ring and Pinion Set - 3.73 Ratio - 29 Spline Pinion - 1.875 in. Diameter Pinion Bearing Journal - Rear.