Q: How should the transmission fluid and Transmission Filter be drained and replaced on Chevrolet Express?
A: At specified intervals, the transmission fluid should be drained and replaced, ensuring the engine has cooled down completely before starting the procedure. Purchase the required transmission fluid along with a new filter and pan gasket prior to beginning work. Necessary tools include a floor jack, jackstands for vehicle support, a drain pan with at least an eight-quart capacity, newspapers, and clean rags. Raise the vehicle securely on jackstands and remove the heat shield next to the catalytic converter to access the pan bolts on the right side. Place the drain pan underneath the transmission pan, remove the front and side mounting bolts, and loosen the rear bolts. Carefully pry the transmission pan loose with a screwdriver to allow the fluid to drain, then remove the remaining bolts, pan, and gasket, cleaning the gasket surface thoroughly. Drain the fluid from the pan, clean it with solvent, and dry it with compressed air if available, noting that some models have magnets in the pan to catch metal debris, which should be cleaned thoroughly. Remove the filter and filter seal from the valve body, taking care not to damage the aluminum surface, then install a new seal and filter. Ensure the gasket surface on the transmission pan is clean, install a new gasket, position the pan against the transmission, and tighten all bolts gradually to the specified torque. Reinstall any components removed for access, lower the vehicle, and add approximately four quarts of the specified automatic transmission fluid through the filler tube. With the transmission in Park and the parking brake set, run the engine at a fast idle without racing it, then move the gear selector through each range and back to Park, allowing the engine to idle for a few minutes before checking the fluid level, adding more fluid as necessary to reach the proper mark on the dipstick while avoiding overfilling. Finally, check under the vehicle for leaks during the first few trips and verify the fluid level again when the transmission is hot.