Generally, when snow or mud is present on the driving surface, it is the right time to engage your on-demand or part-time 4WD system. If you have an all-time system like Quadra-Trac I, there is no input required from you. In heavy snow, when pulling a load, or for additional control at slower speeds, shift the transmission to a low gear and shift the transfer case to 4WD-LOW if necessary (Quadra-Trac I and Quadra-Trac SRT do not offer a low range). Don't shift to a lower gear than necessary to maintain momentum. Over-revving the engine can spin the wheels and traction will be lost. If you begin to lose traction in snow or mud, turn your steering wheel back and forth rapidly. This will generally help the wheels bite into fresh terrain and pull you through. If traction is lost, STOP. Wheel spinning will just dig you in deeper. The key is to maintain forward momentum.