- Welcome to Truck Component Services - your home of heavy truck used parts and chassis. We deal in heavy duty truck parts, including diesel engines, transmissions, oil pans, flywheel housings, crankshafts, ECM's, exhaust manifolds and more. Our huge heavy duty truck parts inventory is unbeatable in terms of selection and price! Our Web site features online specials and online request for you to be able to let us know what you are looking for. Be sure to take advantage of these and the rest of the site's features.