1988 Ford F Series Trucks Ring and Pinion Set F-150 - 4WD - Ford 8.8 in. Rear - Ring and Pinion Set - 5.71 Ratio - 30 Spline Pinion - Requires Notched Cross Pin Shaft - Rear guaranteed to replace your current 1988 Ford F Series Trucks Ring and Pinion Set F-150 - 4WD - Ford 8.8 in. Rear - Ring and Pinion Set - 5.71 Ratio - 30 Spline Pinion - Requires Notched Cross Pin Shaft - Rear. 1988 Ford F Series Trucks Ring and Pinion Set comes new OEM 1988 Ford F Series Trucks Ring and Pinion Set aftermarket new 1988 Ford F Series Trucks Ring and Pinion Set of remanufactured 1988 Ford F Series Trucks Ring and Pinion Set F-150 - 4WD - Ford 8.8 in. Rear - Ring and Pinion Set - 5.71 Ratio - 30 Spline Pinion - Requires Notched Cross Pin Shaft - Rear.