Explore the XWD system Haldex (Fourth generation) on a Saab 9-3X in Jukkasjärvi with Jan Tammpere, Project Manager The New Saab 9-3 X and Kaj Zachrisson, Extreme Skier. Saab introduced a combination of Haldex Couplings on Saab 9-3 Turbo X in late 2007, called XWD (Cross-Wheel Drive).
The main components of the new Haldex system are the Power Take-Off Unit (PTU), Limited Slip Coupling (LSC) and eLSD (Electronic Limited Slip Differential).
The PTU is the final drive unit at the front of the vehicle that transmits power to the front wheels and sends power down the driveshaft to the rear wheels. It is not a Haldex design, but is required to adapt the system to a front-wheel drive vehicle.
The LSC sits at the rear of the vehicle in-line with the driveshaft. It controls the torque split between the front and rear wheels of the vehicle. The LSC sends torque to the eLSD that sits between the rear wheels.
The eLSD transfers torque to the two rear wheels. Follow the jump to continue reading more about the system.
Saab XWD Haldex 4.0 all-wheel-drive system looks simple but it’s very complex. Experience of Haldex on VAG cars is that they need oil changing every 2 yrs and oil and filter every 4 years. But, Saab recommend NO maintenance on their Haldex unit. Is this system really so good?
In this video, we can see Saab XWD in Slow Motion on Ice road:
A little more about this system: