CSF High-Performance auxiliary radiator for the BMW G8X M2, M3 and M4. Its TIG-welded aluminum tanks are larger than the OE plastic units for more strength and fluid volume, and a 2-row 42mm core with CSF's exclusive B-Tube technology and 5mm fins increases cooling capacity and recovery. It is a true drop-in that fits both the left and right side, uses OEM-style quick-connect fittings, and includes a detachable rock guard. Sold individually; all applications use two auxiliary radiators.
| Type | High-performance auxiliary radiator (CSF B-Tube) |
| Core | 2-row, 42mm |
| Fins | 5mm multi-louvered |
| Material | All-aluminum, 100% TIG-welded tanks |
| Inlet / Outlet | OEM-style quick-connect |
| Fit | True drop-in; fits both left and right side |
| Finish | Satin black |
| Included | Detachable rock guard |
| Warranty | 2-year limited warranty |
This part fits:
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2024-2025 | BMW | M3 | Competition xDrive |
| 2024 | BMW | M3 | CS |
| 2021-2026 | BMW | M4 | Base |
| 2021-2026 | BMW | M4 | Competition |
| 2022-2026 | BMW | M4 | Competition xDrive |
| 2025 | BMW | M4 | CS |
| 2023 | BMW | M4 | CSL |
