An important Off-Road accessory for all solid axle-equipped off-road vehicles is the heavy-duty differential cover. The HD Diff Cover protects the Ring & Pinion from damage where one of the tightest tolerance torque maneuvers happens. The Ring & Pinion is where the engine’s torque gets turn 90-degree to drive the axle shafts. With the precision of the tolerances being so tight is why the H3 Hummer needs the protection for aggressive off-road trails.
I used to suggest a different HD Diff Cover because it was inexpensive and worked great. However, after watching the Power Banks videos on YouTube where they test different HD Diff Covers it became apparent that cavitation is something that most manufacturers do not take into account very well. This is why I swap out the old one and bolt-on ARB’s 0750007B Differential Cover which I purchased through Amazon. Just ignore that Amazon suggests that the ARB diff cover doesn’t fit both the H3 and H3T Hummer. I personally have had the Diff Cover on my H3 Hummer for a while now and is performing its job of protecting my ring & pinion perfectly.
In my opinion, the ARB 0750007B Differential Cover is simply the best design out there that can be purchased for the H3 Hummer. “ARB differential covers are powder coated either red or black, CNC machined, then clear coated for a durable, professional, long-lasting finish.” The high-power neodymium magnets also referred to as rare earth magnets, on both the dipstick and drain plug perform a great job collecting any loose ferromagnetic particles that may be loose in the oil. Preventing potential damage to the ring & pinion.