GMC Sierra 2014 Owner's Manual page 78

3-18 Seats and Restraints
4. Be sure that the belt is not
twisted and it lies flat. The
elastic cord must be under the
belt and the guide on top.
5. The elastic cord on the comfort
guide is adjustable. Make it
longer or shorter by squeezing
both ends of the plastic adjuster
and pulling on the elastic cord or
the guide.
6. Adjust the guide so the shoulder
portion of the belt is on the
shoulder and not falling off of it.
The belt should be close to, but
not contacting, the neck.
Improper comfort guide
adjustment could reduce the
effectiveness of the safety belt in
a crash.
Warning
A safety belt that is not properly
worn may not provide the
protection needed in a crash. The
person wearing the belt could be
seriously injured. The shoulder
belt should go over the shoulder
and across the chest. These parts
of the body are best able to take
belt restraining forces.
7. Buckle and position the safety
belt as described previously in
this section. Make sure that the
shoulder belt crosses the
shoulder.
To remove and store the comfort
guide, squeeze the belt edges
together so that the safety belt can
be removed from the guide. Unhook
the guide from the loop on the seat.
Store the guide in a convenient
place like the glove box for the next
time it is needed.