CSF High-Performance Auxiliary Radiator – BMW M2 / M3 / M4 (F8x) #8258

OVERVIEW

The CSF #8258 High-Performance Auxiliary Radiator is a substantial upgrade over the OEM auxiliary radiator on the F8X-chassis M2 Competition/CS, M3 and M4. TIG-welded aluminum tanks replace the factory plastic tanks for greater strength and fluid capacity, and the core steps up from the OEM single-row design to a 2-row, 42mm high-performance core built on CSF's exclusive B-Tube technology, with ultra-efficient multi-louvered fins for maximum surface area contact and heat rejection.

Construction is 100% aluminum throughout for performance and long-term durability. The unit is multi-fit — the same radiator works on both the left and right side of the car — and includes a detachable bolt-on rock guard to protect the core from road debris. Every unit is individually leak and pressure tested. A satin black finish keeps a clean OEM+ appearance behind the grilles.

This is a true drop-in fit using the OEM-style quick-connect inlet and outlet fittings and factory mounting points, requiring no modification to install.

SPECS

• 2-row, 42mm high-performance core featuring CSF's exclusive B-Tube technology
• Ultra-efficient multi-louvered fins for maximum surface area contact and heat dissipation
• Increased tank volume and core size over OEM
• 100% all-aluminum TIG-welded construction
• OEM-style "quick connect" inlet and outlet
• Multi-fit — fits both left and right side
• Includes detachable bolt-on rock guard
• Individually leak and pressure tested
• True drop-in fit — requires no modifications to install
• Satin black finish
• Replaces OEM part numbers 17-11-2-284-603 and 17-11-2-284-604
• 2-year limited warranty

PARTS INCLUDED

• One (1) CSF #8258 high-performance auxiliary radiator
• Detachable bolt-on rock guard
• Complete kit as supplied by CSF Radiators; see the installation instructions supplied in the box for the full bill of materials.

TECH RESOURCES

Additional Parts Required

• A second CSF #8258. The radiator is sold individually and every application requires two — order quantity 2 for a complete installation.
• Coolant for refilling and bleeding the cooling system after installation (installer supplied).
• No other additional hardware is required. CSF specifies a true drop-in fit using the OEM quick-connect lines and mounting locations.

Installation

• CSF does not publish a downloadable installation PDF for this part. Printed installation instructions are supplied in the box.
• Installation requires no modification to the vehicle; the radiator is multi-fit and mounts on either side using the supplied mounting hardware.

Notes

• Sold individually — all applications require two auxiliary radiators.
• Year ranges and trims follow CSF's current published application table for #8258. This part was split out from a multi-SKU draft listing that bundled it with CSF #8179, #8321 and #8355 under one product with variants; those three part numbers already have their own individual Speed Logic listings, so this SKU has been given its own listing to match.

PART NUMBER

• 8258 — CSF BMW F8X M3/M4/M2 Comp High-Performance Auxiliary Radiator (satin black)

VEHICLE APPLICATIONS