Hobbies Cars & Motorcycles How to Operate Your Truck's 4 Wheel Drive System Share PINTEREST Email Print Marin Tomas/Getty Images Cars & Motorcycles Trucks Cars Motorcycles Used Cars SUVs ATVs & Off Road Public Transportation By Dale Wickell Dale Wickell is an automotive expert who has worked in the industry for more than four decades. He currently works for LeMay - America's Car Museum. our editorial process Dale Wickell Updated December 07, 2018 It doesn't take long to learn when and how to use your truck's 4WD system. Follow these steps and you'll feel confident about engaging the system the next time you need to get out of a slippery situation. Four-wheel drives use higher and lower ranges to optimize forward movement for severe off-road driving conditions, like climbing over boulders, crossing streams, and tackling steep hills with loose gravel. But when do you engage it and how? For a conventional system, where you can select 2WD or 4WD, your truck's manual instructions describe how you shift out of 2WD and into 4WD. For trucks with permanent 4WD, the manual refers to locking the center differential to make the shift. Make sure to have your owner's manual on hand. How to Operate Your Truck's 4 Wheel Drive System Refer to your owner's manual to find out the precise steps to engage your truck's 4WD mechanism. When driving in snow, mud, or just going off the road, shift into 4WD at the point when you get ready to leave solid ground. If you have lockable front hubs, lock them for those operations now. For the most severe conditions, use low range if you have it available. Before shifting into low range you must either stop or slow down to at least 3 mph to prevent grinding gears. When you return to normal conditions, shift back out of 4WD or unlock the center differential. If the shifter doesn't want to move from 4WD or the differential lock stays engaged, don't panic, because the problem is normal and is caused by pressure on the gears. Try backing in a straight line about 10 feet and try to move the shifter again. If the shifter still won't move, try backing in an "S" pattern while trying to move the shifter. If you have lockable hubs, don't forget to unlock them when you return to dry pavement. Tips Vehicles with permanent 4WD are set up for everyday driving, but not necessarily for maximum traction on slick surfaces. Engaging the differential lock increases the vehicle's traction capabilities. Do not operate a locked 4WD on dry, hard surfaces. Doing that could cause damage to the driveshafts, differentials or transfer case.