Ford Focus Owner's Manual page 178

Roadside Emergencies
Tire change procedure
When one of the front wheels is off the ground, the transaxle
alone will not prevent the vehicle from moving or slipping off the
jack, even if the vehicle is in P (Park) (automatic transaxle) or R
(Reverse) (manual transaxle).
To help prevent the vehicle from moving when you change a tire,
be sure the parking brake is set, then block (in both directions)
the wheel that is diagonally opposite (other side and end of the
vehicle) to the tire being changed.
If the vehicle slips off the jack, you or someone else could be
seriously injured.
Do not attempt to change a tire on the side of the vehicle close
to moving traffic. Pull far enough off the road to avoid the
danger of being hit when operating the jack or changing the wheel.
1. Remove the spare tire and jack by
turning their tie-down bolts
counterclockwise. The lug wrench is
located in a bag next to, or on top
of, the spare tire.
2. Block the diagonally opposite
wheel.
178
2008 Focus (foc)
Owners Guide (post-2002-fmt)
USA (fus)