Who doesn’t love unlikely mashups? Hulk and Thor, Run DMC and Aerosmith and that cheetah that’s friends with a dog. All of which are awesome mashups and prove that when two parties, however unlikely, come together for a common good, great things can happen. BMW is a brand that seems to be teaming up with a lot of car companies, as of late. However, it seems that keeping these partnerships is proving to be a bit difficult.

BMW’s most famous partnership is with Toyota, both of which are developing the BMW Z4/Toyota Supra together. Although, BMW did most of the engineering heavy lifting and both cars will actually be assembled by Magna. However, there were also rumors of a small-car architecture being co-developed by BMW and Toyota, a project that’s seemingly fallen flat. Differences in opinion and poor timing have led to halts between the two automotive giants.

There were also rumors a while back of the Bavarians and McLaren possibly working on a supercar. The idea was the McLaren would make the chassis while BMW would style the exterior and interior while also helping to develop the engine. It was supposed to be a joint collaboration between McLaren and the M Division. In fact, M Division CEO Frank van Meel even spent some time in Woking this past summer, with McLaren. However, according to Automobile, the venture fell through and isn’t going to happen. “It’s a great piece of kit,” acknowledged a senior BMW manager. “But we came to the conclusion that it is the wrong car for these fast moving times.”

The Bavarians were also said to be working on a new joint-venture with bitter rival Daimler. Since the dawn of time, BMW and Daimler have gone head-to-head. Though it seems that the two companies were working on settling their differences for a common goal, to develop two new scalable architectures. Though, a cartel scandal over diesel engines and AdBlue caused Daimler to self-indict and come clean, without telling BMW ahead of time. So BMW has put their joint-venture on hold for the time being. The financial upside of the deal might still cause BMW and Daimler to go through with it but it won’t be an enthusiasts partnership, at least on the side of BMW.

It seems that BMW is unafraid of partnering with other brands to get things done. Even bitter cross-town rivals. However, it also seems that this is trickier than it sounds.