BMW's all-wheel-drive midsize sport utility vehicle debuted in winter of 1999-2000 as the V8-powered X5 4.4i, with a manually shiftable five-speed automatic transmission. A lower-priced six-cylinder 3.0i edition arrived in spring 2000 with a standard five-speed manual transmission and optional four-speed automatic. Both models have been built in South Carolina, on an exclusive unibodied platform. All X5s came with standard permanently engaged four-wheel drive, traction control, an antiskid system, all-disc antilock braking, and a tailgate with separate lift glass. Lacking low-range gearing, the four-wheel-drive system is not intended for severe off-road use. Instead, it automatically brakes individual wheels to limit slippage in low-grip conditions. A standard hill descent control feature limits speed to 6 mph down steep slopes. Standard equipment included a power tilt/telescopic steering wheel, 70/30 split folding rear seat, and front side-impact airbags. BMW's head-protecting tubular airbags deploy from above front door windows in a side impact. Rear lower-body side airbags were optional. Included on the 4.4i and optional for the 3.0i were a load-leveling suspension, 18-inch wheels and tires, leather upholstery, and wood interior trim. An available Sport Package consisted of black exterior trim, a sport suspension and, for the 4.4i, 19-inch tires. Either model could have an optional navigation system with dashboard-mounted video screen. Rivals include the Acura MDX, Lexus RX 300, and Mercedes-Benz M-Class.