Ford 1999 F-350 Owner's Manual page 156

Roadside emergencies
5. Loosen each wheel lug nut
one-half turn counterclockwise but
do not remove them until the wheel
is raised off the ground.
When one of the rear
wheels is off the ground,
the transmission alone will not
prevent the vehicle from moving
or slipping off the jack, even if the
transmission is in P (Park)
(automatic transmission) or R
(Reverse) (manual transmission).
To prevent the vehicle from
moving when you change the tire,
be sure that the parking brake is
set and the diagonally opposite
wheel is blocked.
If the vehicle slips off the jack, you or someone else could be
seriously injured.
The following steps apply to F250/F350 only:
6. Insert the hooked end of the jack
handle into the jack and use the
handle to slide the jack under the
vehicle.
7. Position the jack according to the
following guides:
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