GMC SIERRA CK2 1999 Owner's Manual page 274

Front Position
7. Lower the vehicle by rotating the ratchet and wheel
wrench counterclockwise. Lower the jack completely.
5-28
Rear Position
8. Tighten the nuts
CAUTION:
Incorrect wheel nuts or improperly tightened
wheel nuts can cause the wheel to become 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. See "Capacities and
Specifications" in the Index.
yellowblue
firmly in a crisscross
sequence as shown
by rotating the wheel
wrench clockwise.