Brake Caliper BMW X3 F25 X4 F26 Rear Brake Housing Left N/S 42/20 6791017

BMW X3 F25 X4 F26 Left Rear Brake Caliper 42/20 is an original part from the brake calipers and brackets category, designed for the rear left axle in BMW vehicles. It ensures stable braking force and proper operation of the rear axle system, translating to safe and predictable vehicle handling. This is a solution for users seeking a part structurally matched to a specific mounting position in the vehicle.

Specifications and technical data

• SKU: 6791017
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 6791017
• Substitutable numbers: 6791017, 34216791017
• Location on the vehicle: Rear, Left
• Category: Calipers & Brackets

Intended Use and Vehicle Placement

The presented brake caliper is designed for operation on the rear left side of the vehicle. Correct placement on the vehicle is crucial for maintaining even distribution of braking forces and proper cooperation with other elements of the braking system.

Dedication to specific BMW X3 F25 and X4 F26 models means that the geometry of the mounts, spacing, and body construction are adapted to the manufacturer's factory requirements. This ensures the caliper works with the discs and pads intended for these models, without the need for modifications or adaptations.

Technical and Functional Characteristics

The brake caliper is responsible for converting hydraulic system pressure into clamping force of the pads against the disc. The rear left version used in the BMW X3 F25 and X4 F26 has been constructed to provide:

• stable pad-to-disc clamping force during emergency braking and daily use,
• proper cooperation with the braking force distribution system on the rear axle,
• adequate body stiffness, limiting deformation under high loads.

The 42/20 designation refers to the specific technical configuration of the caliper, matched to the braking system used in these BMW models. This ensures the component maintains correct operating parameters across the full load range specified by the manufacturer.

Benefits of Using an Original BMW Caliper

Choosing a caliper designed for specific BMW models offers a range of practical advantages:

• Factory Fitment – maintaining original mounting geometry and compatibility with other braking system components.
• Consistency with Safety Systems – proper operation with braking assistance systems, such as electronic stability control or brake force distribution systems.
• Predictable Vehicle Behavior – even braking of the rear axle, contributing to vehicle stability during speed reduction.

A part from the brake calipers and brackets category, selected for a specific axle and side of the vehicle, minimizes the risk of installation problems and improper system operation. This is particularly important in BMW-class cars, where driving precision and braking effectiveness are key aspects of the vehicle's characteristics.

Product Condition and Practical Application

The offered brake caliper is a used part, allowing for an economical component replacement while maintaining compliance with BMW's factory specifications. This type of solution is often chosen for comprehensive rear braking system service when caliper replacement is necessary due to mechanical wear or damage.

In practice, installation involves removing the old caliper, connecting the brake line, properly bleeding the system, and checking the piston and guide operation. After installation, a road test is recommended to verify even braking and the absence of unwanted noises.

Selecting Used Brake System Components

When choosing a used caliper for a BMW, it's worth paying attention to compliance with manufacturer markings and vehicle placement. Practical tips found in the article: Used Braking System: How to Safely Select Discs, Calipers, and ABS? can be helpful. This is a comprehensive checklist that facilitates assessing whether a given part will be suitable for a specific car.

If you want to further care for the longevity of disassembled components, it's also worth reading the guide: How to Extend the Lifespan of Used Car Parts, which describes practical methods for maintaining and properly servicing such elements.

Other BMW Brake Calipers and Brackets

If you are also looking for other BMW brake calipers and brackets suitable for various models of this brand, check the available assortment in our catalog: BMW brake calipers and brackets. This will allow you to easily compare available variants and select a complete solution for your car's entire braking system.