Radiator, CSF Triple-Pass Aluminum - E39 540i/M5

BimmerWorld View - Unique three-pass design maximizes cooling. CSF builds an industry leading, high-quality, all aluminum drop-in radiator that exceeds OE standards, gets rid of the plastic end tanks, and improves cooling by 25-30%.

We trust CSF quality and performance in our street and track cars to provide proper cooling with an easy direct-fit install. This E39 540i/M5 radiator is a factory replacement using all factory shrouding, clip-on hoses, and mounting points.

CSF uses new technology packed into a compact two-row design for better cooling capacity without the added weight. More efficient B-tubes have greater surface area for cooling (15% cooling capacity increase in fin technology alone) and a precision multi-louvered fin to increase heat rejection performance and surface area contact. Additionally, this CSF part has more total cooling tubes, and a three-pass flow design for maximum cooling in race environments and extreme driving conditions - an E46 M3 industry first.

These technical features all contribute to improved cooling efficiency over OE-type performance upgrades, as well as other standard "performance" aluminum tanked radiators which are nothing more than aluminum tanks on a traditional stock core.

Read more about B-Tube technology (PDF)

Made in Indonesia in the same factory that produces CSF parts for aftermarket and car line production for several European cars. This part is a much higher level of quality than the typical Chinese factory parts. CSF's Racing & High Performance Division is able to produce a premium high performance cooling system with a level of quality and craftsmanship that is usually found in products with a much higher price point due to their economies of scale of over 600,000 units sold globally every year.

540i Fitment Note: fits manual transmission models with no modification. Will fit automatic transmission models with slight modification to drain plug.

INSTALLATION NOTE: Any radiator replacement can result in air pockets during initial installation/filling which will not allow the system to function properly. Special care must be taken to fully bleed all air in radiator, engine, and cooling system before operation.

All CSF radiators come with a two year warranty against defects in craftsmanship.