Find the Gear Oil and friction modifier you need for your 2017-2019 Chevy/GMC 6.6L L5P Duramax. With 85W-140, 80W-140, 80W-90, 75W-140 or 75W-90 available, you'll find the lube you need for your application. You find a broad selection of conventional, synthetic blend, and full synthetic lubes are available. Top manufactures like Royal Purple, Lucas Oil, AFE, Motorcraft, and Nitro Gear & Axle are available at XDP.