PPE GM 2500 HD Cast Aluminium Rear Differential Cover – Black | Silverado 2500HD & 3500HD

Increase differential cooling, improve lubrication and strengthen your rear driveline with the PPE GM 2500 HD Cast Aluminium Rear Differential Cover. Designed for 2020+ Chevrolet Silverado and GMC Sierra HD models equipped with the AAM 11.5" or 12" 14-bolt rear differential, this premium upgrade increases oil capacity while replacing the factory stamped-steel cover with a heavy-duty cast aluminium alternative.

The PPE GM 2500 HD Cast Aluminium Rear Differential Cover has been engineered to improve differential cooling, increase oil capacity and provide superior protection for the rear differential assembly.

Whether you're towing heavy caravans, carrying constant loads or travelling remote Australian tracks, differential temperatures can increase significantly under sustained load. The PPE cover increases differential oil capacity by approximately 0.7 quart (0.66 litres) while improving heat dissipation through extensive external cooling fins and specially engineered internal oil control features.

Manufactured from premium A356.0-T6 heat-treated cast aluminium, the cover provides significantly greater rigidity than the factory stamped-steel cover while offering increased resistance to impacts from rocks, road debris and off-road hazards.

Internally, precision-engineered windage scrapers reduce excessive oil churning and aeration, helping maintain lubricant stability while reducing heat generation. External cooling fins work in conjunction with the internal design to maximise heat dissipation and strengthen the housing.

Servicing is improved with 304 stainless steel magnetic fill and drain plugs, both incorporating high-temperature neodymium magnets to capture ferrous wear particles before they circulate through bearings and gears. A dedicated 1/8" NPT port also allows installation of an optional differential temperature sender.

Key Features:

• Heavy-duty A356.0-T6 cast aluminium construction.
• Durable black powder-coated finish.
• Suits GM AAM 11.5" & 12" 14-bolt rear differential.
• Approx. 0.7 quart (0.66L) additional oil capacity.
• Large external cooling fins.
• Internal windage scrapers reduce oil churning.
• Increased housing rigidity.
• Improved underbody protection compared to the factory stamped-steel cover.
• Magnetic 304 stainless steel fill and drain plugs.
• High-temperature neodymium magnets.
• 1/8" NPT temperature sender port.
• Limited lifetime manufacturer warranty.

Why Upgrade?

Differential oil performs best when it remains cool and free from contamination.

The PPE differential cover helps by:

• Increasing differential oil capacity.
• Improving heat dissipation.
• Lowering differential operating temperatures.
• Extending gear oil life.
• Improving lubrication under sustained load.
• Providing increased protection from rocks and road debris.
• Capturing metallic wear particles before they circulate through the differential.

Ideal for:

• Caravan towing.
• Heavy towing.
• Touring.
• Off-road use.
• Commercial vehicles.
• Fleet applications.

Vehicle Fitment:

Chevrolet Silverado:

• 2500HD.
• 3500HD.
• 6.6L Duramax L5P.
• AAM 11.5" or 12" 14-bolt rear differential.
• 2020+

GMC Sierra:

• 2500HD.
• 3500HD.
• 6.6L Duramax L5P.
• AAM 11.5" or 12" 14-bolt rear differential.
• 2020+

Always confirm axle compatibility before ordering.

What's Included:

• PPE Rear Differential Cover.
• Magnetic Fill Plug.
• Magnetic Drain Plug.
• Mounting Hardware.
• Installation Instructions.

Installation Notes:

• Direct replacement for the factory differential cover.
• Differential oil refill required.
• RTV sealant or gasket as specified by the man.ufacturer.
• Optional temperature sender sold separately.
• Professional installation recommended.

Why We Recommend It:

At Garage76, we recommend differential upgrades for vehicles that regularly tow, tour or work in harsh Australian conditions.

The PPE Rear Differential Cover improves cooling, increases lubricant capacity and strengthens one of the hardest-working components in the driveline. Combined with magnetic filtration and improved serviceability, it's a worthwhile reliability upgrade for protecting expensive differential components over the long term.