Peterbilt 379 388 389 Fiberglass Cowl Panels Are you looking to replace or upgrade your Peterbilt 379, 388, Or 389 cowl panels? These 6" or 8" cowl panels are made from fiberglass and are sold as a pair. Cowl Panel Fits Various Peterbilt 379, 388, And 389 Trucks (Choose Model/Year Range Ab... See More