XDP has a large assortment of stock replacement and upgraded parts for the Allison 1000 (5-Speed Automatic) or ZF S6-650 (6-Speed Manual) Transmission in your 2001-2004 GM Silverado/Sierra 2500HD/3500HD. The Allison Light Commercial Truck (LCT) 1000 Transmission was a popular choice among buyers and has earned an excellent reputaiton over the years. If you are increasing the power levels of your Chevy/GMC Duramax-powered truck, modifications can be done to upgrade your Allison to withstand the increased power levels. DPC, Sun Coast Converters, and ATS offer Torque Converters that will handle competition-level horsepower and torque. Upgraded Flex Plates will handle greater power and allow for better power transfer from the Torque Converter. Enhance the shifting of your transmission with a Valve Body from Revmax, BD-Power, or ATS. Hardened input, output, and intermediate Automatic Transmission Shafts are a massive upgrade for your stock transmission. Automatic Transmission Pans from XDP, Mag-Hytec, and PPE will help extend the transmission fluid life by keeping it cool.
A manual style transmission is typical in older diesel trucks, requiring the driver to make all of the gear selections on their own. Find top Transmission Fluid brands like Royal Purple, Lucas Oil, and Champion you need for your Automatic or Manual Transmission. Manual Transmission Clutches from Valair or South Bend Clutch come with single, dual, and triple clutch plates to handle any power level. Replace the worn-out Manual Transmission Hydraulics to improve clutch engagement and disengagement. Upgrade your transmission's input shaft with XDP's Manual Transmission Shafts. Find the parts you need to keep your transmission on the road with the products available at XDP.