2005 Ford F250 Owner Guide 3rd Printing - Page 205

Driving Always set the parking brake fully and make sure the gearshift is latched in P (Park). Turn the ignition to the LOCK position and remove the key whenever you leave your vehicle. If the parking brake is fully released, but the brake warning lamp remains illuminated, the brakes may not be working properly. See your dealer or a qualified service technician. 4WD Systems 4WD (when you select a 4WD mode), uses all four wheels to power the vehicle. This increases traction, enabling you to drive over terrain and road conditions that a conventional two-wheel drive vehicle cannot. Power is supplied to all four wheels through a transfer case. On 4WD vehicles, the transfer case allows you to select 4WD when necessary. Information on transfer case operation and shifting procedures can be found in the Driving chapter. Information on transfer case maintenance can be found in the Maintenance and Specifications chapter. You should become thoroughly familiar with this information before you operate your vehicle. Normal characteristics On some 4WD models, the initial shift from two-wheel drive to 4x4 while the vehicle is moving can cause some momentary clunk and ratcheting sounds. This is the front drivetrain coming up to speed and the automatic locking hubs engaging and is not cause for concern. Sand When driving over sand, try to keep all four wheels on the most solid area of the trail. Avoid reducing the tire pressures but shift to a lower gear and drive steadily through the terrain. Apply the accelerator slowly and avoid spinning the wheels. If you must reduce the tire pressure for whatever reason in sand, make sure you re-inflate the tires as soon as possible. Avoid excessive speed because vehicle momentum can work against you and cause the vehicle to become stuck to the point that assistance may 205 2005 F250/350/450/550 (f23) Owners Guide (post-2002-fmt) USA_English (fus)