Chevrolet 2003 Impala Owner's Manual page 336

5-80
7. Tighten the wheel nuts
firmly in a crisscross
sequence as shown.
{
CAUTION:
Incorrect wheel nuts or improperly tightened
wheel nuts can cause the wheel to come loose
and even come off. This could lead to an
accident. Be sure to use the correct wheel
nuts. If you have to replace them, be sure to
get new GM original equipment wheel nuts.
Stop somewhere as soon as you can and have
the nuts tightened with a torque wrench to the
proper torque specification. See "Capacities
and Specifications" in the Index for wheel nut
torque specification.