We upgraded the leaking transmission pan on this E92 M3's DCT transmission with the Turner Motorsports High Capacity Pan (008789LA03KT). It's a cast aluminum unit with integrated cooling fins, which when combined with the increased capacity (about 1L). This is a well-priced upgrade that one might want to consider if you're already planning to do your MDCT Filters and Fluids. We replaced both the side filter and the in-pan filter (OEM filters are compatible with this pan) and filled the gearbox with Motul's latest High-Torque DCTF ester based fluid (#110440).
There's no secret to keeping a transmission, be it manual or automatic, reliable on track or even when canyon carving, more fluid and better cooling will increase the durability of this gearbox under high load environments. It's also common for these gearboxes to sweat from the side pan, mechatronics plug, and the bottom pan, so a little extra capacity doesn't hurt. Future serviceability is also improved as a proper metal threaded drain plug is included.
We would like to note that due to the extended capacity pan being lower, the undertray piece that covers the transmission pan will need to be bent a little to fit. It's also important to note that ground clearance is reduced so if you live in an area with rougher roads and exposed manhole covers, extra attention may be needed.
