AMC Model 20 12-Bolt Aluminum Differential Cover - Polished

• Polished aluminum finned cover only for AMC Model 20 rear axle housings, 12-bolt cover pattern

• AMC Model 20 uses a 12-bolt cover with an 8-bolt ring gear — confirm both specs before ordering

• Drain plug included; gasket and mounting hardware not included — cover only, not a kit

• Fits Jeep CJ, AMC Javelin, AMC AMX, and Jeep J-Series truck applications

This is a polished aluminum finned differential cover built for AMC Model 20 rear axle housings — the rear end used across Jeep CJ-series vehicles, AMC Javelin, AMC AMX, AMC Matador, and Jeep J-Series trucks. The AMC Model 20 uses a 12-bolt cover pattern with an 8-bolt ring gear — both specs should be confirmed against your axle before ordering, since the cover bolt count and ring gear bolt count differ and are often referenced independently when cross-shopping covers.

This listing is for the cover and drain plug only — gasket and mounting hardware are not included. If you need a complete installation kit, TSP also offers this cover as a kit with gasket and hardware included (SP4906KIT). Confirm your sealing method (cut gasket or RTV) and source hardware separately before starting installation.

The finned aluminum construction dissipates heat more effectively than a flat steel cover, helping reduce gear oil temperature during sustained trail, towing, or performance use. A polished finish adds show-quality appearance for builds where underbody aesthetics matter.

Polished Finned Aluminum Cover for the AMC Model 20 — Cover and Drain Plug Only
This finned aluminum differential cover is sized and bolted for AMC Model 20 rear axle housings with a 12-bolt cover pattern, finished in polished aluminum for a clean, show-quality appearance on CJ Jeep, AMC muscle car, and Jeep J-Series truck builds. A drain plug is included; gasket and mounting hardware are not.

Fins Dissipate Heat, Aluminum Saves Weight Over Stock Steel
Unlike a flat steel factory cover, the finned aluminum design increases surface area to help dissipate heat from gear oil during sustained use — trail driving, towing, or performance applications where the rear axle sees extended load. Aluminum construction also reduces unsprung weight compared to a steel cover.

What axle does this cover fit?
This differential cover is designed for AMC Model 20 rear axle housings, commonly found on Jeep CJ-series vehicles, AMC Javelin, AMX, Matador, and Jeep J-Series trucks.

How many bolts does this cover use?
This cover uses a 12-bolt cover pattern. The AMC Model 20 also uses an 8-bolt ring gear, so the cover bolt count and ring gear bolt count are different. Verify both specifications before ordering.

What's the difference between this listing and the SP4906KIT?
This SP4906 listing includes the polished aluminum differential cover and drain plug only. The SP4906KIT includes the cover, gasket, mounting hardware, and drain plug for a complete installation package.

Does this come with a gasket?
No. A gasket and mounting hardware are not included with this listing. Purchase them separately or choose the SP4906KIT for a complete installation kit.

Is a drain plug included?
Yes. A drain plug is included with this differential cover.

Will this fit a Jeep CJ?
Yes. The AMC Model 20 rear axle was commonly used on Jeep CJ-5, CJ-6, CJ-7, and CJ-8 Scrambler models. Verify your specific axle before ordering.

Will this fit a Jeep Wrangler YJ or TJ?
No. Jeep Wrangler YJ and TJ models typically use Dana 35 or Dana 44 rear axles and are not compatible with this AMC Model 20 differential cover.

Why choose a finned aluminum cover over a standard steel cover?
The finned aluminum design helps dissipate heat more efficiently than a conventional steel cover, helping reduce gear oil temperatures during demanding driving conditions. Aluminum construction also weighs less than steel.

Will this fit a GM or Ford rear axle?
No. This cover is designed specifically for AMC Model 20 rear axles and is not compatible with GM or Ford axle assemblies.

What should I verify before installing this cover?
Verify the axle model, 12-bolt cover pattern, 8-bolt ring gear, housing shape, sealing method (gasket or RTV), fill plug location, fluid capacity, and suspension clearance before installation.