FORD 2011 F-550 v.2 - Manual (Page 288)

once the engine has developed sufficient drive to prevent the vehicle
from rolling down the slope. This is an advantage when pulling away on a
slope; for example from a car park ramp, traffic lights or when reversing
uphill into a parking space.
WARNING: The hill start assist feature does not replace the
parking brake. When you leave the vehicle, always apply the
parking brake and select first or reverse gear.
Using hill start assist
The hill start assist feature is activated automatically when the vehicle is
stopped on a slope greater than five degrees. The hill start assist feature
operates with the vehicle facing downhill if reverse gear is selected. The
hill start assist feature will not operate if the parking brake is activated.
WARNING: You must remain in the vehicle once you have
activated the hill start assist feature.
Activating hill start assist
1. Press the brake pedal to bring the vehicle to a complete standstill.
Keep the brake pedal pressed.
2. If the sensors detect that the vehicle is on a slope, the hill start assist
feature will be activated automatically.
3. When you remove your foot from the brake pedal, the vehicle will
remain on the slope without rolling away for approximately up to two
seconds. This hold time will automatically be extended if you are in the
process of driving off.
4. Drive off in the normal manner. The brakes will be released
automatically.
WARNING: If the engine is revved excessively, or if a
malfunction is detected when the hill start assist feature is
active, the hill start assist feature will be deactivated.
If your vehicle gets stuck in mud or snow
If your vehicle gets stuck in mud or snow, it may be rocked out by
shifting between forward and reverse gears, stopping between shifts in a
steady pattern. Press lightly on the accelerator in each gear.
Driving
288
2011 F-250/350/450/550 (f23)
Owners Guide, 2nd Printing
USA (fus)