GMC 2007 Sierra 1500 Pickup Owner's Manual page 577

CAUTION:
{
Never use oil or grease on studs or nuts.
If you do, the nuts might come loose.
Your wheel could fall off, causing a
serious accident.
9. Put the wheel nuts back on with the rounded
end of the nuts toward the wheel.
10. Tighten each wheel nut by hand. Then use
the wheel wrench to tighten the nuts until the
wheel is held against the hub.
Front Position - All Models
577