BMW G20 G21 G22 G42 B48 Automatic Gearbox GA8HP51Z 5A04AA2 WARRANTY

Listing details

The gearboxes are sold with a 90-day warranty! They were tested before removal and are in full working order.

BMW G20 G21 G22 G42 B48 Automatic Gearbox GA8HP51Z is an advanced automatic transmission designed for modern BMW models with diesel engines. This used transmission from this series ensures smooth gear shifts, high operational refinement, and stable torque transfer during daily use. It is a solution for users who expect a proven design while maintaining a reasonable service budget.

Specifications and technical data

• SKU: 5A04AA2
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 5A04AA2
• Substitutable numbers: 5A04AA2, 24005A04AA2, 24009456491, 9456491, 24005A8C0C7, 5A8C0C7
• Fuel type: Diesel
• Gearbox type: Automatic
• Part type: Automatic Transmission
• Category: Automatic Transmission

Application and compatibility

The presented automatic transmission has been designed to work with the Diesel power unit in BMW G20, G21, G22, and G42 series models with the B48 engine. The transmission design is adapted to the torque characteristics of modern engines, which translates into stable acceleration, predictable throttle response, and comfortable driving both in city traffic and on the highway.

Automatic gear control allows for reduced jerking and lowers the load on the drivetrain, which is particularly important during dynamic operation. The transmission belongs to the Automatic transmissions category, making it a perfect fit for the requirements of drivers who expect convenience and repeatable performance parameters.

Construction and operating characteristics

The GA8HP51Z automatic transmission has been engineered for precise gear control and efficient use of engine power. The applied architecture allows for fast yet smooth gear changes, which improves driving comfort and reduces energy losses in the drivetrain. Properly selected gear ratios support both calm, economical driving and a more dynamic driving style.

Cooperation with a diesel engine requires resistance to high torque and stable operation under a wide range of loads. This automatic transmission was designed specifically for such conditions, ensuring predictable vehicle behavior, good kick-down response, and efficient downshifts when overtaking.

Benefits of installing a used automatic transmission

Using a used automatic transmission in a G-series BMW allows for a significant reduction in repair costs compared to a brand-new component, while maintaining the correct operating parameters of the drivetrain. This solution is particularly beneficial in the event of major failures, where repairing the existing transmission is unprofitable or time-consuming.

The main advantages of installing such a transmission include:

• Restoring proper drivetrain operation – restoring smooth gear shifting and the vehicle's correct dynamics.
• The ability to match the specific engine-transmission configuration in a given BMW model, in accordance with the manufacturer's markings.
• Reduction of service downtime thanks to a ready-to-use component that, after proper installation and adaptation, can quickly return to service.

Professional installation and part selection

To fully utilize the potential of this automatic transmission, installation in a specialized service center is recommended, which will ensure proper connection to the drivetrain, correct oil filling, and adaptation procedures. Proper selection of the transmission for a specific vehicle is facilitated by the manufacturer's markings and available interchangeable numbers, which allow for verifying compatibility with a given model.

If you are planning a comprehensive repair or upgrade of the drivetrain area in your BMW and need other elements from the same group, such as a converter, control elements, or additional transmission components, check the available parts in the BMW automatic transmissions category.

Technical support and selecting a used transmission

When choosing a used automatic transmission, it is worth paying attention to the compatibility of markings, fuel type, and transmission type, as well as the installation and adaptation procedures required for a given model. A detailed discussion of the differences between manual, automatic, and DSG transmissions, typical faults, and the rules for safely purchasing a used transmission can be found in the article Transmission: manual, automatic or DSG – typical faults and a guide to buying a used transmission, which provides a practical supplement to technical information and helps in making an informed service decision.