For those who are comfortable driving at the limit, Dynamic Stability Control now includes, for the first time in a BMW SUV, Dynamic Traction Control. A button lets the driver choose a higher threshold of wheel-slip before DSC engages, and though this technique is good for starting off on loose snow, it can also be used to turn the X3 into even more of a driving machine.
The new six-speed automatic proved to be as smooth and precise in normal, everyday driving as last year's five-speed automatic. Just put it in Drive and go. When pushing it in the slippery stuff, the automatic frees the driver to focus on braking, accelerating and steering. This can be a lot of fun. When so inclined, the driver can use the Steptronic feature to hold the transmission in a specific gear, manually shifting up or down as the incline or traction dictates or invites.
The six-speed manual transmission, on the other hand, is everything people who know and like BMWs have come to expect and appreciate. Shifts are smooth and precise, clutch engagement predictable and gears properly spaced to keep the engine in the sweet spot of its power band, although it is geared a bit high for relaxed long distance cruising. We prefer the automatic.
Acceleration is still silky and linear, it just happens more quickly now, thanks to the new 3.0-liter inline six-cylinder engine's 260 horsepower, 35 more than the outgoing six. The power delivery is also smoother because of Valvetronic, BMW's sophisticated control system that helps optimize engine response while also reducing fuel consumption. The 3.0si records 0-60 mph times of 6.9 seconds for the manual and 7.1 seconds for the automatic. While not blistering performance figures, they are significant improvements over the 2006 X3 and, considering the vehicle's weight, are no cause for shame.
The optional Servotronic steering is flat-out wonderful. It's speed-sensitive, adding more assist at low speeds, and invisibly altering the steering ratio, so the car turns more with less steering input. Parallel-parking is a breeze, as are quick, mid-block U-turns. As speed increases, assistance diminishes and the ratio slows, making for good on-center feel and sure lane changes. Perhaps the best thing about the Servotronic steering is its transparency; unless a driver moves directly from the X3 to another vehicle without the feature and suddenly has to crank in more steering at slow speeds, it'll likely not be noticed at all.
Braking is smooth and sure, with solid pedal feel allowing linear, gradual stops when desired, unlike many over-assisted systems increasingly popular on high-end cars and SUVs. BMW usually accompanies engine upgrades with improvements to such dynamic elements as braking and handling, and it's just so with the X3 3.0si.
The X3 doesn't offer the quietude of a Lexus, but BMW owners are forgiving of a bit more exhaust note or suspension feedback, and from that perspective the 2007 X3 is virtually fault-free. The new powertrain is smoother and quieter than before, erasing an irritating exhaust drone we experienced in the previous model at certain cruising speeds. Wind noise reaches levels that are surprising for a BMW, until you look at the speedometer and realize you're going faster than you realized. This isn't a svelte sedan that hunkers close to the pavement, so a bit of wind noise in return for the X3's eagerness to eat up miles of open road without breaking a sweat is acceptable.
The xDrive system uses an electronically controlled array of clutches to disperse the engine's torque among the four wheels the instant it's needed, even to the point of sending 100 percent of the traction to any single wheel. Dynamic Stability Control (DSC) works to rein in the car when it's over-extended in cornering or emergency maneuvers; electronic throttle control reduces engine power when necessary to regain traction. The antilock brake system (ABS), allows the driver to maintain steering control in a panic braking situation. Electronic brake-force distribution (EBD) improves braking performance by adjusting front/rear brake balance. Dynamic Brake Control, or Brake Assist, recognizes emergency brake application and maintains full braking force even if the driver mistakenly relaxes pressure on the brake pedal. Next Page