NEW TECHNOLOGY CREATES JEEP 4X4 CAPABILITY
An electronically controlled coupling (ECC), which is attached to the Patriot’s rear differential, is the heart of Jeep Patriot’s Freedom Drive I and Freedom Drive II Off-road Package four-wheel-drive systems. Patriot’s ECC system is easier to calibrate, more flexible, more precise and lighter than viscous-coupling or gerotor systems.
The ECC transmits torque to the Patriot’s rear wheels through a two-stage clutch system. An electromagnet powered by current from the electronic control module operates a low-torque clutch. A cam-and-ball mechanism amplifies the force of the low-torque clutch, applying the main clutch that transmits torque to the rear wheels. The control module calculates vehicle speed, turning radius and wheel slip and transfers torque based on these conditions. The unit seamlessly interacts with the Electronic Stability Program (ESP), Anti-lock Brakes (ABS) and Brake Traction Control systems to ensure torque is transferred as needed, providing better handling and traction characteristics.
Unlike other on-demand four-wheel-drive systems that rely on pumps or viscous fluids to transfer torque, the Jeep Patriot’s four-wheel-drive system requires no front-to-rear slippage for activation. Patriot’s state-of-the-art electronic four-wheel-drive system anticipates the need for added traction and responds to wheel slippage by automatically transferring power to the rear wheels. The system contributes to Patriot’s excellent fuel economy by operating only when needed, minimizing power-robbing friction and inertia.