Chevrolet Express Owner's Manual page 332

10. Turn the jack handle
counterclockwise to lower the
vehicle. Lower the jack
completely.
Wheel nuts that are not tight can
work loose. If all the nuts on a
wheel come off, the wheel can
come off the vehicle, causing a
crash. All wheel nuts must be
properly tightened. Follow the
rules in this section to be sure
they are.
If wheel studs are damaged, they
can break. If all the studs on a
wheel broke, the wheel could
come off and cause a crash.
If any stud is damaged because
of a loose-running wheel, it
could be that all of the studs are
damaged. To be sure, replace all
studs on the wheel. If the stud
holes in a wheel have become
larger, the wheel could collapse in
operation. Replace any wheel if
its stud holes have become larger
or distorted in any way. Inspect
hubs and hub piloted wheels for
damage. Because of loose
running wheels, piloting pad
damage may occur and require
replacement of the entire hub, for
proper centering of the wheels.
When replacing studs, hubs,
wheel nuts or wheels, be sure to
use GM original equipment parts.
(Continued)
Wheel nuts that are improperly or
incorrectly tightened can cause
the wheels to become loose or
come off. The wheel nuts should
be tightened with a torque wrench
to the proper torque specification
after replacing. Follow the torque
specification supplied by the
aftermarket manufacturer when
using accessory locking wheel
nuts. See
original equipment wheel nut
torque specifications.
for