Range Function

WARNING: This page is about a different car, the 2005 Mercury Mountaineer and 2005 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.

In 4x4 Low, 4x4 High, and all wheel drive (AWD) modes, the 4WD control module uses throttle input and vehicle speed to determine control of the transfer case electromagnetic clutch. The transfer case shift motor rotates the shift cam to move the reduction shift fork to the 4x4 Low range position. This low range shift, accomplished through a planetary gear set, changes the torque to the drive shaft from 1:1 to 2.48:1 ratio.

In the 4x4 High range, with throttle input, the 4WD control module signals the transfer case electromechanical clutch to lock the front and rear driveshafts for maximum 4-wheel drive traction. Never use the 4x4 High range or the 4x4 Low range when driving on dry or merely wet pavement. Use 4x4 High range or the 4x4 Low range only for driving off-road or in severe winter weather.