In the past, Bmw labeled their vehicles with straightforward designations. The initial digit represented the series and the second and third the referred to engine displacement. Sometimes an extra letter may be provided, but that would be it. Later, however, they began using different letters such as M, Z and X for the SUVs with xDrive (AWD).
So at present there are labels such as X6 xDrive 35i. But it did not end there. Bmw will now give rear-wheel-drive variants, which used to be their whole line-up, the “sDrive” name in addition to any other designation they may stick on it.
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