There are significant differences between German axles and American axles in terms of design, performance characteristics, maintenance and shaft head shape:

1.Design complexity: The design of German axles is generally more complex than that of American axles, aiming to meet the requirements of lightweight and long-lasting performance. 

2.Brake drum surface design: The surface of the brake drum of German axles is usually equipped with reinforced ribs. These designs enhance the strength of the brake drum and avoid cracking or deformation. At the same time, it increases the air flow speed, improves heat dissipation efficiency, and avoids overheating failure.

3.Maintenance and accessories: The accessories used in German axles are not common with American axles and need to be purchased separately. Even the grease is usually made using German-specific products.

4.Axle head shape: The shape of the axle head of German axles is relatively complex, usually in an irregular conical shape. This design can reduce the weight of the axle beam, ensure lightweight characteristics, and at the same time enhance the stability of the axle head and components, reducing operation clearance to improve efficiency and longevity.

5.Brand and market application: The brands of German axles are mainly high-end brands such as bpw. These axles are mainly used in industries with high vehicle requirements such as cold chain transportation, tobacco, and precision instruments. The American axle brands are mainly Fuhua and Darong. The American axle 13-ton disc brake axle on the market is very popular. 

6.Braking system: German-style axles have good braking effects and are stable at high speeds, while American-style axles have disc brake systems that are more sensitive, have better heat dissipation and braking effects than drum axles, and can improve driving safety with the ABS system.

7.Suspension type: Suspension is divided into rigid suspension and air suspension. Rigid suspension has strong load-bearing capacity and is cheap, while air suspension has strong comfort and good stability, but the price is higher. The policy stipulates that three-axle ramp trucks and gate trucks must be equipped with disc brakes and air suspension before they can be licensed, which increases the cost of use for truck drivers.

To sum up, there are obvious differences between German axles and American axles in terms of design, performance, maintenance, axle head shape, brand, braking system and suspension type.