Gf had an 05 735li, 3.6l v8. Again, nice car, but f*cking pricey to maintain and fix. It had a common fault, that I found mentioned about the x5 engines too as they're all similar, where a coolant pipe/seal in the middle of the valley fails, 10k to fix through bmw supposedly, a mob in the US made a part so it could be done for 2-3k. Needed all the front removed, radiator out, inlet manifold off etc. Ended up just trading it in with the water leak.