BMW 1 Series E82 E88 135i Front Left / Right N/O/S Wheel Brake Disc 338X26

The BMW 1 Series E82/E88 135i Front Brake Disc is an original BMW braking system component, designed for installation on the front axle, on either the left or right side. Thanks to its precise fit for the 135i version and robust construction with a working diameter of 338 mm and a thickness of 26 mm, it ensures stable braking system operation and predictable vehicle behavior during intensive braking. This is a solution for users who want to maintain factory braking parameters and consistency with the original BMW specification.

Specifications and technical data

• SKU: 6778647
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 6778647
• Substitutable numbers: 34116778647, 6778647, BG
• Location on the vehicle: Front, Left, Right
• Category: Brake Disc Rotors

Application and Compatibility

The presented brake disc is designed for BMW 1 Series E82 and E88 models in the 135i version, where a brake system with a disc diameter of 338 mm and a thickness of 26 mm is factory-fitted. The design is intended for installation on the front axle, with the possibility of use on both the left and right sides, which facilitates selection and servicing of the system.

Original BMW origin means maintaining the correct geometry, offset, and working surface, which translates to proper cooperation with the calipers and brake pads intended for the 135i version. This provides the driver with predictable, repeatable braking system responses, without the need for modifications to other components.

Construction and Operating Parameters

The brake disc with a diameter of 338 mm and a thickness of 26 mm has been designed with the dynamic characteristics of the BMW 135i in mind. These dimensions provide adequate friction surface area and thermal mass, contributing to braking stability at higher speeds and during repeated, strong decelerations.

Key functional features of this disc include:

• working diameter of 338 mm – optimized for factory BMW 135i calipers,
• thickness of 26 mm – ensuring adequate rigidity and heat dissipation capacity,
• dedicated mounting for BMW 1 Series E82/E88 hubs – no modifications required.

A disc configured in this way allows for maintaining stable braking parameters and even pad wear, which is important for both safety and operational economy.

Characteristics of a Used Component

The offered brake disc is a used part, meaning it is a pre-owned component that retains its original BMW specification. For many users, this represents a favorable compromise between cost and maintaining factory quality of workmanship and fit. A used OEM disc is particularly attractive in situations where consistency with the original braking system and the ability to compare with existing components by part numbers is a priority.

Choosing an original, used brake disc allows for maintaining braking system performance characteristics close to factory settings, without the risks associated with using random aftermarket parts with uncertain parameters.

Benefits of Using an Original BMW Brake Disc

Using this disc in the BMW 1 Series E82/E88 135i offers a number of practical benefits:

• Factory Fitment – maintaining original geometry and braking system operating parameters.
• Compatibility with other system components – proper cooperation with calipers and pads intended for the 135i version.
• Predictable vehicle behavior – stable braking during daily driving and dynamic use.
• Verifiable by OEM and reference numbers – easier part selection based on specific vehicle configuration.

For owners of the BMW 135i who want to keep their car in line with factory specifications, choosing an original disc from this series is a technically safe solution consistent with the manufacturer's intentions.

Brake System Expansion and Part Selection

If you are planning a comprehensive repair or upgrade of the braking area in your BMW and need other parts from the same group, such as additional discs, compatible pads, or brake lines, check the available parts in the BMW Brake Discs category.

When selecting used braking system components – especially discs, calipers, and ABS system components – it is advisable to follow a proven verification procedure. Practical tips on how to safely assess the condition of such parts and select them for a specific model can be found in the article “Used Brake System: How to Safely Select Discs, Calipers, and ABS?”, which serves as a useful checklist for informed users.

For those interested in a broader approach to operating used, original components in BMW cars, the material describing the impact of such parts on durability and driving precision may also be helpful – more information can be found in the article “BMW – Sporty Performance and Precision. How Used Original Parts Extend the Life of the Bavarian Icon?”.