BMW E82 E88 125i N52N Rear Differential Diff 3,73 Ratio 7590237 7591107 WARRANTY

Listing details

The differential is sold with a 90-day warranty! It was tested before removal and is in full working order.

BMW E82 E88 125i N52N Rear Differential Diff 3,73 Ratio is an original rear differential with a 3.73 gear ratio, designed for installation in the drive axle of the BMW 1 Series. This item belongs to the Differentials category and is a key component of the drivetrain, responsible for properly distributing torque to the rear wheels. Thanks to its factory design, it ensures the vehicle maintains the manufacturer's intended driving dynamics and characteristics.

Specifications and technical data

• SKU: 7591108
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 7591108
• Substitutable numbers: 33107591108, 7591108, 33107591107, 7591107, 33107590238, 7590238, 33107590237, 7590237
• Location on the vehicle: Rear
• Category: Differentials

Purpose and function in the drivetrain

The presented rear differential is designed to operate in the rear of the vehicle within the BMW N52N engine drivetrain. As a rear axle differential, it is responsible for:

• transferring torque from the driveshaft to the half-shafts,
• compensating for the difference in wheel rotational speed during cornering,
• maintaining stable traction during acceleration and engine braking.

Selecting a differential with a specific 3.73 ratio allows for maintaining the factory drivetrain tuning, which translates into predictable vehicle behavior and consistent operation with the stock gearbox.

Benefits of using an original differential

An original differential from disassembly is a solution that, in many cases, allows for a technically correct repair while keeping costs reasonable. Compared to aftermarket replacements or modifications, this component offers:

• factory geometry and fitment for the mounting points in the BMW E82/E88 chassis,
• compatibility with the stock driveshaft and half-shafts,
• preservation of the original acceleration characteristics and engine RPM at a given speed.

As a result, installation is predictable, and the risk of mechanical or geometric compatibility issues is minimized.

Condition, origin, and service application

The differential comes from disassembly and is offered as a used original BMW part. This type of component is particularly useful in situations where:

• the existing differential has suffered mechanical damage (e.g., noise, seizure, excessive play),
• it is necessary to replace the complete assembly instead of undergoing costly refurbishment,
• you want to restore the car to factory specifications after previous gear ratio modifications.

Choosing a complete rear differential with the correct ratio simplifies the service process – the mechanic replaces the entire assembly without the need to swap ring gears or adjust backlash in a different housing.

Gear ratio selection and vehicle configuration compatibility

The 3.73 ratio is an important parameter affecting driving characteristics – acceleration, flexibility, and engine RPM at highway speeds. Proper selection of the differential for the specific engine version and gearbox of the BMW 125i N52N is crucial for:

• avoiding errors in the operation of electronic systems (ABS, DSC, cruise control),
• maintaining correct speedometer readings,
• maintaining acoustic comfort during steady driving.

To better understand the relationship between the differential ratio and driving style, it is worth checking out the guide: Drivetrain axles and differentials from disassembly – how to choose ratios for your driving style, where practical configuration examples and the most frequently asked questions are discussed.

Support with selection and BMW drivetrain upgrades

If you are planning a comprehensive repair or upgrade of the drivetrain in your BMW and need other parts from the same group, such as differential housings, driveshafts, or additional differentials with different ratios, check out the available parts in the BMW Differentials category.

Before purchasing, it is recommended to verify the compatibility of the differential with the specific equipment version and model year of the car to ensure trouble-free installation and proper cooperation with the existing drivetrain.