Shop Differential Covers and upgrade the front or rear axle in your 2004.5-2005 Chevy/GMC 6.6L LLY Duramax. Aftermarket cast covers typically offer increased fluid capacity, integrated cooling fins, and additional strength over the OE stamped steel cover. Differential Covers are often available as an upgraded cast and machined design or as a stock stamped steel replacement. Shop all the top brands including Mag-Hytec, Dynatrac, ATS Diesel, BD-Power, PPE, AFE Power, Yukon, Banks Power, B&M, Nitro Gear & Axle, Dorman, and more!