1999 GMC P3500 Ring and Pinion Set RWD - GM 10.5 in Rear - w/ 14 Bolt Cover - 3.21 Ratio - Ring and Pinion Set - Fits 3 series 4.10 & Down Carrier - Rear guaranteed to replace your current 1999 GMC P3500 Ring and Pinion Set RWD - GM 10.5 in Rear - w/ 14 Bolt Cover - 3.21 Ratio - Ring and Pinion Set - Fits 3 series 4.10 & Down Carrier - Rear. 1999 GMC P3500 Ring and Pinion Set comes new OEM 1999 GMC P3500 Ring and Pinion Set aftermarket new 1999 GMC P3500 Ring and Pinion Set of remanufactured 1999 GMC P3500 Ring and Pinion Set RWD - GM 10.5 in Rear - w/ 14 Bolt Cover - 3.21 Ratio - Ring and Pinion Set - Fits 3 series 4.10 & Down Carrier - Rear.