AAM 12 Inch Ring Gear Differential Cover for GM Trucks – Heavy Duty Aluminum Upgrade

Enhance the strength and protection of your drivetrain with this AAM 12 Inch Ring Gear Differential Cover for GM Trucks, designed to deliver superior durability and improved cooling under demanding conditions. Ideal for towing, hauling, and heavy-duty applications, this upgraded cover helps safeguard your differential while maintaining optimal performance.

Constructed from high-quality aluminum, this differential cover provides increased strength compared to factory stamped covers. The rugged design helps protect internal components from damage while improving heat dissipation to keep your differential operating at optimal temperatures.

Engineered as a direct-fit replacement for GM trucks equipped with AAM 12 inch ring gear differentials, this cover ensures reliable sealing, enhanced durability, and long-lasting performance.

✅ Key Features:

• Fits AAM 12 inch ring gear differentials on GM trucks
• Heavy-duty aluminum construction for strength and durability
• Improves heat dissipation and cooling
• Provides added protection for internal components
• Ideal for towing, hauling, and heavy-duty applications
• Direct fit for easy installation and leak-free sealing

Upgrade your differential with confidence and ensure maximum durability and performance in demanding conditions.

Volume: about 0.5 quarts over 2020 stock GM truck cover

Dimensions: Click here for dimensions. 

Number of Bolts: 14

Description: 2020 and newer GMC/Chevy heavy duty trucks have a new version of the American Axle Manufacturing (AAM) 14 bolt differential. The ring gear may be 12 inches or 11.8 or 11.5.

Pictures of PML new AAM 14 Bolt for 2020 and newer Silverado and Sierra 2500 and 3500 trucks:

      
Part shown in natural as cast finish and in black powder coat finish. Click on image to view larger.

This new American Axle differential has a cover very similar in shape and bolt hole pattern to the cover on 2001 to 2019 trucks. But the covers and gaskets are not the same and not interchangeable.

Benefits:

• Drain and magnetic drain plug included
• Heavy duty, sand cast aluminum
• Finned for heat dissipation
• Works with brake line bracket, no modification needed
• About 3/8 inches deeper than stock for clearance to sway or pan hard bars
• Shape similar to stock cover
• Extra capacity

Applications:

GM vehicles that probably have these new differentials:

• 2020 GMC Sierra 2500 and 3500 trucks
• 2020 Chevrolet Silverado 2500 and 3500 trucks

Configurations vary. Always check your vehicle to verify differential and clearance.

The GM gasket part number for this differential is 68454491AA.

This includes trucks with the Allison transmission.

For 2019 and older trucks with the AAM 11.5, 11.8 differential, see PML part number 9511.

PML Cover Compared to GM Stock Cover

PML cover next to GM stock cover, outside and inside.

   
Click on image to view larger.

Stock Covers and Gaskets

2020 GMC Sierra 2500 Gas Engine Stock Rear Differential Cover:

  Click on image to view larger.

2020 and newer GM HD truck stock cover (outside, inside, part number):

      
Click on image to view larger.

For comparison, here is the 2001 to 2019 stock differential cover:

  Click on image to view larger.

2019/2020 and Newer Gasket (GM gasket part number 68454491AA) and Gasket for Prior AAM 11.5, 11.8 Differentials:

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