The transmission will automatically downshift to M3 when coming to a dead stop. The lowest it will ever downshift to is M3, assuming that the factory software has not been altered. It will not shift down to M1. Also it will automatically up-shift to the next available gear at red-line so you do not over-rev and cause damage to the engine.

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2004 BMW X5 4.4i-Sports Package-Premium-140,000 Miles