CSF BMW 2 Series (F22/F23) / BMW 3 Series (F30/F31/F34) / BMW 4 Series (F32/F33/F36) A/T Radiator

When you're looking to keep your BMW 2 Series, 3 Series, or 4 Series (F2X/F3X chassis) running cool, especially if you've added more power or plan on hitting the track, this all-aluminum radiator from CSF is a solid choice. It's designed to replace your stock automatic transmission radiator, and CSF has been making cooling components for over 50 years, so they know their stuff. This radiator is built to handle the demands of both street driving and more spirited track use.

What sets this radiator apart is its construction. It features a 2-row, 42mm core that uses CSF's unique "B-tube" technology. Unlike standard oval tubes, these B-tubes are engineered to increase the heat transfer surface area by about 15%, essentially acting like two smaller tubes in one. This design, combined with ultra-efficient, multi-louvered fins precisely aligned to maximize airflow, helps reject heat much more effectively. The brackets and fittings are CNC machined for a precise fit and durability, and the inlet and outlet connections are designed to use your original hoses and hardware, making it a true drop-in replacement that requires no modifications to install. It even includes a smooth satin finish and an all-aluminum race-style drain plug.

This radiator is designed to fit a range of BMW models, including the 2 Series (like the 228i), 3 Series (like the 320i and 335i), and 4 Series (like the 428i and 435i) with automatic transmissions. You can reuse your original AC condenser, fan shroud, and mounting brackets, simplifying the installation process. Trust CSF's experience to keep your engine performing at its best.