Jeep Active Drive I—available on Sport, Latitude, and Limited models—is a fully automatic, single power-takeoff unit system said to improve both under and oversteer conditions, deliver yaw control, and offer balanced torque distribution via the braking system. Jeep Active Drive II is also available on Sport, Latitude, and Limited models, and offers a two-speed PTU with low range. Selecting 4-Low mode locks the front and rear driveshafts and provides a 2.92:1 gear reduction for maximum torque and pulling power. When teamed with the four-cylinder engine, Active Drive II provides a 56:1 crawl ratio; the crawl ratio with the V-6 is 47.8:1. This system also pulls off the brake-based torque-apportioning trick. The third system, Jeep Active Jeep Drive Lock, is standard on the Trailhawk, and adds a locking rear differential to all of the Active Drive II features for better low-speed traction.