2009 Ford F250 Owner's Manual - Page 288

Driving D (Overdrive) with Tow/Haul OFF D (Overdrive) with Tow/Haul OFF is the normal driving position for the best fuel economy. The overdrive function allows automatic upshifts and downshifts through gears one through five. D (Overdrive) with Tow/Haul ON The Tow/Haul feature improves transmission operation when towing a trailer or a heavy load. All transmission gear ranges are available when using Tow/Haul. To activate Tow/Haul, press the button on the end of the gearshift lever. The TOW HAUL indicator light will illuminate in the instrument cluster. Tow/Haul delays upshifts to reduce frequency of transmission shifting. Tow/Haul also provides engine braking in all forward gears when the transmission is in the D (Overdrive) position; this engine braking will slow the vehicle and assist the driver in controlling the vehicle when descending a grade. Depending on driving conditions and load conditions, the transmission may downshift, slow the vehicle and control the vehicle speed when descending a hill, without the accelerator pedal being pressed. The amount of downshift braking provided will vary based upon the amount the brake pedal is depressed. To deactivate the Tow/Haul feature and return to normal driving mode, press the button on the end of the gearshift lever. The TOW HAUL light will no longer be illuminated. When you shut-off and restart the engine, the transmission will automatically return to normal D (Overdrive) mode (Tow/Haul OFF). WARNING: Do not use the Tow/Haul feature when driving in icy or slippery conditions as the increased engine braking can cause the rear wheels to slide and the vehicle to swing around with the possible loss of vehicle control. 288 2009 F-250/350/450/550 (f23) Owners Guide, 3rd Printing USA (fus)