BMW F20 F21 F30 F31 Rear Axle Brake Braking Caliper Housing Left N/S 6850858

BMW F20 F21 F30 F31 Rear Axle Brake Braking Caliper Housing Left N/S is an original BMW braking system component, designed for installation on the left side of the rear axle. This solution is intended for users who expect precise fitment, stable braking system performance, and compliance with the vehicle's factory design.

Specifications and technical data

• SKU: 6850857-4
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 6850857
• Substitutable numbers: 6850857, 34216850857, 6850860, 34216850860
• Location on the vehicle: Rear, Left
• Part type: Brake Caliper
• Category: Calipers & Brackets

Purpose and compatibility with BMW models

The presented brake caliper is a caliper housing designed for the left rear axle in popular BMW F-series models, such as the F20, F21, F30, and F31. Thanks to a design consistent with the manufacturer's factory standards, it ensures proper positioning of the brake pads relative to the disc, which translates into stable and predictable braking system operation. The component belongs to the Brake Calipers and Brackets group, meaning it is responsible for maintaining brake pad clamping force and the correct guidance of moving parts within the rear axle. Using an original BMW component reduces the risk of compatibility issues and facilitates service work.

Technical and functional characteristics

The left rear caliper housing has been designed to operate in demanding conditions – in an area exposed to contaminants, moisture, and variable temperatures. The design ensures:

• stable mounting to the steering knuckle and other rear axle suspension components,
• proper guidance of brake pads relative to the disc,
• the ability to service and replace the caliper's working parts,
• maintenance of braking system geometry in accordance with BMW specifications. Thanks to the use of original geometry and mounting points, installation in place of a worn or damaged component proceeds in an orderly manner, without the need for modifications or adaptations.

Benefits of using an original, used caliper

Choosing an original used BMW brake caliper is a reasonable compromise between cost and quality. The component retains its factory design parameters while allowing for significant cost savings compared to a new part. This is particularly important during comprehensive rear axle maintenance when more than one component is being replaced. A used caliper from the Brake Calipers and Brackets group, after proper installation preparation, can provide long-term and stable braking system performance, provided it is installed correctly and used with functional pads and discs. For many BMW users, this is an effective way to maintain a high level of safety while keeping service costs under control.

Professional installation and part selection

Due to the importance of the braking system for driving safety, installation by a qualified service center is recommended. They will verify the condition of interacting components such as pads, discs, flexible hoses, and mounting points. Proper selection of the caliper for a specific version of the BMW F20, F21, F30, or F31 should take into account vehicle data and manufacturer markings, which minimizes the risk of improper fitment. To better understand how to safely use original recycled components and how to optimize service costs, it is worth reading the article: Brake calipers under the microscope: how to effectively reduce braking system repair costs.

Expanding the BMW braking system

If you are planning a comprehensive repair or upgrade of the braking area in your BMW and need other components from the same group, such as additional calipers, mounting brackets, or guide supports, check the available parts in the BMW Brake Calipers and Brackets category. In the context of rising service costs, it is also worth considering a broader approach to used OEM components – you will find more practical tips in the guide: how to save on car service by choosing used original parts.