Chevrolet 2009 Silverado Owner's Manual page 77

In Canada, the law requires that forward-facing child
restraints have a top tether, and that the tether be
attached.
You will be using the lap-shoulder belt to secure the
child restraint in this position. Follow the instructions that
came with the child restraint.
1. Move the seat as far back as it will go before
securing the forward-facing child restraint.
2. Put the child restraint on the seat.
3. Pick up the latch plate, and run the lap and shoulder
portions of the vehicle's safety belt through or
around the restraint. The child restraint instructions
will show you how.
4. Push the latch plate into the buckle until it clicks.
Make sure the release button is positioned so you
would be able to unbuckle the safety belt quickly
if necessary.
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