1999 GMC GMC 3500 PICKUP - Transmission, Transaxle Manual Transmission, 4x4, Gasoline, 8-454 7.4L, 60 Months Warranty. Free Shipping, 1 Month Return Policy. Used (Original Equipment Manufacturer). Transmission Tested and Run, covered by warranty. All Transmissions are Shipped as Complete Assemblies including: Transmission; Torque Converter (Automatic Transmissions Only); Oil Pan.