1972 GMC Pick-up Truck Ring and Pinion Set K15/K1500 Pickup - Dana 60 - Standard Rotation - Ring and Pinion Set - 3.73 Ratio - Fits 3 Series Carrier - Rear guaranteed to replace your current 1972 GMC Pick-up Truck Ring and Pinion Set K15/K1500 Pickup - Dana 60 - Standard Rotation - Ring and Pinion Set - 3.73 Ratio - Fits 3 Series Carrier - Rear. 1972 GMC Pick-up Truck Ring and Pinion Set comes new OEM 1972 GMC Pick-up Truck Ring and Pinion Set aftermarket new 1972 GMC Pick-up Truck Ring and Pinion Set of remanufactured 1972 GMC Pick-up Truck Ring and Pinion Set K15/K1500 Pickup - Dana 60 - Standard Rotation - Ring and Pinion Set - 3.73 Ratio - Fits 3 Series Carrier - Rear.