[wtwo3]

Mechanical bits (engine & transmission) are rarely the culprits anymore. Cars have improved in those areas to a point where they are practically bullet proof.

The electronics are the main issue, and one of the reason for reliability problems with the more advanced cars like BMW/Mercedes/Audi. It's also one of the reasons Lexus is so slow to adapt to new technologies. Since reliability is one of Toyota's hallmarks, they only add new technologies into their cars when those technologies have been refined enough to have become reliable. It's why they're so behind in technology.

If you take a look at reliability ratings on CR, you can see BMW is a bit of a mixed bag where Lexus is pretty clear-cut.