Chevrolet 2003 Silverado Owner's Manual page 24

Q:
What's wrong with this?
A:
The shoulder belt is too loose. It won't give nearly
as much protection this way.
1-18
{
CAUTION:
You can be seriously hurt if your shoulder belt
is too loose. In a crash, you would move
forward too much, which could increase injury.
The shoulder belt should fit against your body.