2007 BMW X5 in Sun Valley

Like its predecessor, the second-generation X5 disappoints when it goes off the beaten track. Instead of offering a height-adjustable air suspension, it can be had with such pavement-oriented goodies as active steering, adjustable antiroll bars, and switchable dampers. Instead of mechanical differential locks, it features the latest version of the electronically controlled torque-split-by-demand xDrive four-wheel-drive system. And instead of a low-range transfer case, it boasts a new six-speed manu-matic. The key chassis-related innovation is a new multilink front suspension that provides a smoother ride and better handling. Even when the X5 is equipped with the optional $3600 sport package, which includes extrastiff 255/55HR-19 Michelin Latitude run-flat tires, active roll stabilization, and electronic damping control, it responds to arm-thick transverse ridges and crater-deep potholes in a much more compliant manner than it did before.

Compared with the Mercedes-Benz M-class--its chief rival that is built around the corner in Alabama--the new X5 is still a little firmer, edgier, and more aggressive in the way it translates driver inputs. The four-wheel air suspension offered on the previous model has been dropped due to low demand, but air-sprung rear wheels are standard with the V-8-equipped 4.8i and available on the six-cylinder X5 3.0si. As always, BMW's active steering is an acquired taste. It makes maneuvering the X5 nearly effortless, but expect a learning curve before you're able to dial in precisely the appropriate amount of lock at any given speed. While the active antiroll bars do their thing all by themselves, the driver can stiffen the damper setting by hitting the Sport button.... Read full article