automatic transmission,

In addition to the 555-hp 4.4L turbocharged V8 coupled to a 6-speed automatic transmission, the X6 M also gets an M-tuned all-wheel-drive system, a special suspension and even M-tuned stability programming. Twenty-inch double-spoke wheels are standard, as is the 50i's 16-speaker high-performance stereo, 3-stage heated front seats and an M-specific tilt leather-wrapped steering wheel.