Ventilated Brake Disc BMW E90 E91 Braking Unit Rear Left N/O/S 336X22 6855004

Ventilated Brake Disc BMW E90 E91 Braking Unit Rear Left N/O/S 336X22 is an original BMW braking system component, designed for installation on the rear axle on the left side. This item from the Brake discs category allows for an economical yet technically correct repair of the braking system in 3 Series E9x vehicles.

Specifications and technical data

• SKU: 6855004
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 6855004
• Substitutable numbers: 34216855004, 6855004, 34216764655, 6764655
• Location on the vehicle: Rear, Left
• Category: Brake Disc Rotors

Purpose and compatibility for BMW E90, E91, E92

The presented brake disc has been designed specifically for the E9x platform, ensuring a proper fit with the hub, caliper, and brake pads on the rear axle. Its placement on the rear left side of the vehicle guarantees compliance with the factory braking system geometry, which translates into stable handling and predictable vehicle behavior during braking.

Its original BMW origin ensures that the appropriate manufacturing tolerances are maintained, which is essential for even pad wear, correct caliper operation, and the minimization of steering wheel and body vibrations at higher speeds.

Technical and functional characteristics

As an element from the Brake discs category, the product is responsible for working with brake pads to effectively decelerate the vehicle. The disc design is adapted to the standard braking system of the BMW E90, E91, E92, which allows for maintaining factory performance parameters, such as:

• stability of braking force on the rear axle,
• correct load distribution between the front and rear of the vehicle,
• appropriate friction surface for standard brake pads.

The placement on the rear left side of the vehicle facilitates the selection of the correct component during service – especially when replacing a single disc or during post-collision repairs, where precise identification of the mounting side is required.

Condition, origin, and benefits of choosing a used part

The offered brake disc is a used item, sourced from vehicle dismantling. This type of solution allows for a significant reduction in repair costs compared to purchasing a new component, while maintaining the manufacturer's original specifications. For many users of the BMW 3 Series E9x, this is a reasonable compromise between price and quality, especially for cars used on a daily basis.

Choosing original, used braking system components is often recommended by workshops specializing in the BMW brand, as it ensures compliance with the vehicle's factory parameters and reduces the risk of problems resulting from the use of unsuitable replacements.

Safety, selection, and service aspects

When replacing the rear brake disc in a BMW E90, E91, E92, it is worth paying attention to:

• selecting the appropriate brake pads that work with the given disc,
• checking the condition of the calipers, guide pins, and brake lines,
• checking axial and radial runout after installation.

Professional installation and correct tightening of fastening elements are of key importance for driving safety. In case of any doubts regarding part selection or the installation procedure, it is worth consulting a specialized BMW service or an experienced mechanic dealing with braking systems.

Additional information on how to reasonably use components from dismantling in the braking system is provided in the article: Brake calipers under the microscope: How to effectively reduce braking system repair costs by choosing proven recycled parts, which discusses practical aspects of safety and cost optimization.

Braking system expansion and other BMW brake discs

If you are planning a comprehensive repair or upgrade of the braking zone in your BMW and need other elements from the same group, such as additional rear discs, front discs, or compatible disc and pad sets, check the available parts in the BMW brake discs category.

If you are considering broader modifications to your car, including retrofitting elements from higher trim versions, the following retrofit guide may also be helpful: Retrofitting in VAG and BMW group cars: How to cheaply equip a car using used parts from higher versions?, which shows how to effectively use parts from dismantling in modernization projects.