GMC 2007 Envoy - Manual (Page 475)

Secondary Latch System
Your vehicle has an underbody-mounted tire
hoist assembly equipped with a secondary latch
system. It is designed to stop the spare tire
from suddenly falling off your vehicle if the cable
holding the spare tire is damaged. For the
secondary latch to work, the tire must be stored
with the valve stem pointing up. See Storing
a Flat or Spare Tire and Tools on page 478
for instructions on storing the spare or flat tire
correctly.
{ CAUTION:
Before beginning this procedure read all
the instructions. Failure to read and follow
the instructions could damage the hoist
assembly and you and others could get
hurt. Read and follow the instructions
listed next.
{ CAUTION:
Someone standing too close during the
procedure could be injured by the jack.
If the spare tire does not slide off the jack
completely, make sure no one is behind
you or on either side of you as you pull
the jack out from the spare.
To release the spare tire from the secondary latch,
do the following:
1. Check under the
vehicle to see if
the cable is visible.
If it is not visible,
proceed to Step 6.
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