Best Seller | 1979-1986 GMC K3500 Rear Outer Differential Pinion Race - API GMC K3500 Rear Outer Differential Pinion Race. Brand: API. Fits Years: 1979, 1980, 1981, 1982, 1983, 1984, 1985, 1986, 79, 80, 81, 82, 83, 84, 85, 86. PDL -- Spicer 70HD; 10.54" Ring Gear - 4087-07902762 more | | $5.97 go to store |