GMC 2009 Sierra - Manual (Page 22)

Q:
What is wrong with this?
A:
The lap belt is too loose. It will not give nearly as
much protection this way.
{ CAUTION:
You can be seriously hurt if your lap belt is too
loose. In a crash, you could slide under the lap
belt and apply force on your abdomen. This
could cause serious or even fatal injuries. The
lap belt should be worn low and snug on the
hips, just touching the thighs.
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