The original OE oil cooler from BMW is an all metal design which would make you think it would be fairly robust. However, there are several weak spots in the design that tend to cause leaks. The CSF Race-Spec design reinforces the weak points, especially around the feed and return lines. CSF's solid line connection block can handle any abuse thrown at it while the reinforced and braced return tube is rock solid. CSF also upgraded the more fragile Tub/Fin core to a robust and durable Bar/Plate design. The core is 40% larger than the factory unit with 2 additional rows of oil cooling and much thicker core (63mm vs OE 45mm). This offers superior cooling capacity and volume for the oil system. TIG welded end tanks round out the slew of upgrades creating a much stronger connection than the factory brazed construction. CSF offers the best and most advanced Oil Coolers on the market. So when it comes to keeping your engine oil temps down as you push your BMW E60 M5 / E6X M6 hard on the street or track, a CSF Oil Cooler is the obvious choice. The CSF #8275 Cooling product is designed to be a "Drop-In Fit" applications. The product will install in the OEM Location with no modifications necessary unless otherwise noted or instructions are included in the product package. Please see the manufacturer repair manual for standard installation instructions. If you do not feel confident installing this product CSF recommends taking it to a qualified installation facility.