Oil Cooler Upgrade, CSF - E46 M3

The CSF E46 M3 Oil Cooler is a budget-friendly yet high-quality drop-in solution for the constant battle of keeping fluids at their optimal operating temperatures in your M3.

Even in stock trim, the oil in an E46 M3 gets hotter than you might expect. Add additional horsepower and stress on the engine by running it around the track for just 10 minutes straight, and the oil gets extremely hot. Even the best synthetic oils should be kept under 250°F if possible and never above 300 degrees, yet on the E46 M3, the stock cooler just won't get the job done.

CSF's newly designed high-performance, race-spec oil cooler will keep oil temperatures stable, even in the most demanding endurance racing conditions and extreme ambient temperatures. This new CSF E46 M3 oil cooler has been lab tested in an ISO-certified, state-of-the-art cooling system testing facility that includes wind tunnel, vibration, thermal cycle, burst pressure, and salt spray corrosion testing for maximum performance and reliability. Because of CSF's global economies of scale, the CSF Racing & High-Performance Division delivers a premium oil cooling solution with a level of quality, performance, and craftsmanship that is usually found in products with a much higher price point.

Construction and Core: CSF has manufactured the world's most durable and robust E46 M3 oil cooler by using an innovate design that features extruded aluminum end tanks rather than fabricated aluminum sheet metal, plus a bar-and-plate oil cooling core. The core uses an ultra-efficient, multi-louvered, high-density fin configuration between high-pressure oil cooling plates to achieve maximum heat transfer performance and oil cooling efficiency. With this type of construction you never have to worry about road debris damaging the core or causing a leak in the oil cooler.

Capacity: Twice the oil capacity as the OEM unit for additional cooling benefits on top of the core efficiency.

Two-Pass Design: CSF's new E46 M3 oil cooler features an efficient top/bottom dual-pass design which is comparable in performance to a counter-flow design (front/back), without the much more costly manufacturing and purchase price.

Mounting: This production-manufactured high-performance oil cooler utilizes four mounting tabs and two bolts to secure it directly and easily to your stock radiator's mounting points. No fabrication or additional brackets are required. This is a complete drop-in fitment solution which requires no modifications to install.

Plumbing: This is a direct-fit oil cooler for use with existing Genuine BMW S54 oil cooler lines and hoses from your E46 M3. If you use this with an S54 swap in another chassis you have 3 options: stock S54 lines (may require modification*), Euro E36 lines (requires modification**), or custom -10AN lines (requires adapters and custom lines***).

Size & Weight: Approximately 27"L x 3"H x 3"D; 9 lbs
All CSF high-performance cooling systems come with a two-year warranty against defects in craftsmanship or performance. Each CSF cooling system is individually pressure tested before packaging to ensure maximum reliability. This product is designed to be a bolt-on retrofit, but works particularly well in conjunction with the CSF E46 M3 Triple-Pass Performance Radiator or OEM unit.

*the E46 M3 oil cooler lines may need different bends or routing to fit your chassis. This is chassis-dependent.
**the Euro E36 lines do not line up perfectly with the inlets on the oil cooler. You will likely have to remove the bracket on the lines and use the bracket from the AN adapter kit to lock down the lines on the cooler. CSF also recommends doubling up on the AN bracket and the E36 bracket using a longer M8 screw.
***custom lines requires an -10AN adapter at both ends (cooler and oil filter housing). This is the best way to route the lines around the engine bay and clear all accessories.