It is a diff cooling system. uses synthetic oil....not gear lube
Notice the exhaust? It is all stainless and looks like a street car exhaust and they used catalytics on the DTM cars.
The driveshaft is titanium and the flex disc is made of 6-8 layers of Carbon Fiber. There is a special tool (laser) to align the driveshaft to the transmission.
Your picture brings back good memories.
I bet you that car weighs under 900kgs.