Upgrade your Peterbilt 388 with high-performance engine and parts from our comprehensive selection. Boost horsepower, fuel efficiency, and overall driving experience with Bully Dog tuners, FASS fuel systems, and turbochargers for Cummins, Detroit Diesel, and Caterpillar engines. Enhance the sound and appearance of your rig with aluminized steel mufflers, custom exhaust manifolds, and chrome accessories. Whether you're hauling heavy loads or hitting the open road, our Peterbilt 388 parts will help you get the most out of your truck.