
The SHW BRL43853 is a cross-drilled lightweight left rear brake rotor for 2021 BMW M3 / 21-22 BMW M4 (Base/Competition). It measures 370 x 24 mm, weighs 8.2 kg, and is made in Germany. SHW lists OEM reference 34207889663 for this application. It is a straightforward vehicle-specific replacement choice for a brake refresh when you want the correct rotor position, dimensions, and configuration clearly identified.
If the existing disc is worn, scored, heat-checked, damaged, or otherwise due for replacement, confirming the correct rotor specification is an important part of the brake service. This SHW rotor is specified with lightweight construction and a cross-drilled friction surface. Verify the detailed fitment, axle/side, rotor size, and OEM reference before ordering, especially on vehicles offered with multiple brake or wheel packages.
Key Features & Specs:
Fitment: