Heavy-Duty Aluminum Rear Differential Cover - GM-DodgeHelp keep your rear differential running cool and clean with an upgraded differential cover from PPE. Made in the USA from high quality cast aluminum for strength and optimum heat dissipation. Combined with the largest set of cast cooling fins in the industry, found both inside as well as outside the pan, PPEs differential covers offer industry leading fluid cooling. This pan also holds additional fluid, offering thermal stamina for those long hauls.