Considering 2013 X5M with 100k mi and looking for your thoughts?

[crystalworks]

Never had an X5M so can't speak to that particularly.

But for BMW transmissions, specifically the ZF ones, like in the 4.8is and I think all newer (2006+) BMWs... make sure the fluid and filter has been part of the service schedule. BMW screwed future owners after owner 2 (warranty period) by stating the trans is lifetime fill. Causes many trans issues and outright failure leaving the original fluid. ZF recommends 60,000-80,000 miles depending on driving style.

After having to replace the transmission on our 2010 E70 diesel... I've serviced every one of our BMW's trans to avoid that ordeal again. Recently did our E53 4.8is @ 126k miles and it cured the 2-1 gear change slam and some delayed gear changing. Feels like a new vehicle now.