AMC Model 20 Rear Axle with Standard Differential for Case Casting Services Product

For owners and restorers of classic Jeep vehicles, the AMC Model 20 rear axle remains a cornerstone of drivetrain durability. Our Standard Differential Case Assembly for this iconic axle is engineered to provide a reliable, direct-replacement solution that restores original performance and longevity. Manufactured using premium casting services, this product meets the exacting standards demanded by restoration specialists, off-road builders, and vintage Jeep enthusiasts seeking authentic, dependable performance.

Material and Durability Specifications
The differential case is precision-cast from high-strength gray iron (Grade G3500), delivering optimal performance for this classic axle application. This material provides exceptional compression strength and superior vibration-damping characteristics, crucial for maintaining proper gear alignment and ensuring quiet operation. The casting undergoes rigorous normalization heat treatment to stabilize the molecular structure and relieve internal stresses, resulting in a dimensionally stable component with a Brinell hardness rating of 187-241 that withstands the torque requirements of classic Jeep 4-cylinder and 6-cylinder engines.

Precision Manufacturing Process
Our manufacturing process begins with precision sand casting using resin-coated molds that capture every detail of the original design. This method ensures accurate reproduction of the original mounting flange geometry, bolt patterns, and bearing seat locations. Following casting, each component undergoes CNC machining on specialized fixtures to achieve critical tolerances on bearing journals (±0.0005 inches) and ring gear mounting surfaces. This precision manufacturing guarantees perfect ring gear runout specification and proper bearing preload when installed in the Model 20 axle housing.

Performance and Application
This differential case assembly is engineered specifically for the AMC Model 20 rear axle found in Jeep CJ-5, CJ-7, and CJ-8 Scrambler models produced from 1971 through 1986. The design maintains the original equipment specifications for gear mounting and bearing configuration, ensuring correct operation with standard 2.73:1 and 3.31:1 gear ratios. The assembly includes precision-machined spider gears, thrust washers, and cross shaft manufactured to exact OEM specifications, providing complete restoration capability for both street-driven and mild off-road applications.

This authentic reproduction differential case assembly represents the ideal solution for maintaining the original character and capability of classic Jeep vehicles while providing the durability and precision that modern drivers expect.