One problem related to engine head gasket leaking has been reported for the 2011 BMW 335. The most recently reported issues are listed below.
Engine seized 10 miles after oil filter housing gasket was replaced. Car has 107k miles and has been meticulously maintained. Now I'm going to have to spend from $8k-$10k for a new engine. Never received a warning light. From what I've been reading, this is not uncommon after that specific job is done and the gasket starts leaking around 100k so it is necessary to address.