Saab XWD

[1] The XWD is a permanent all-wheel drive system, that can pre-emptively and continuously change torque distribution before wheel slip occurs.

During highway cruising, it can adjust torque distribution, allocating as little as 4% to the rear wheels, a feature intended to improve fuel efficiency.

Additionally, the system is engineered to rapidly transfer torque distribution to the wheel with the most grip, providing immediate traction in various driving conditions.

An ECU continuously collects various data from the car's onboard systems, and in conjunction with the ESC, ABS, and TCS, calculates the best torque distribution in the driveline.

The XWD system debuted on the 2008 limited edition Saab Turbo X, equipped with an electronically controlled limited-slip differential (ELSD), and was gradually made available through the rest of the 9-3 line (in sedan and combi body styles).