GMC 2004 Sierra 1500 Pickup Owner's Manual page 61

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CAUTION:
If the right front passenger's air bag is turned
off for a person who isn't in a risk group
identified by the national government, that
person won't have the extra protection of an
air bag. In a crash, the air bag wouldn't be able
to inflate and help protect the person sitting
there. Don't turn off the passenger's air bag
unless the person sitting there is in a risk
group. See Air Bag Off Switch in the Index
for more on this, including important safety
information.
Securing a Child Restraint in a Rear
Outside Seat Position
Extended Cab and Crew Cab
There is limited space in the rear seating of an extended
cab model. If you want to secure a child restraint in a
rear outside seating position, be sure to study the
instructions that came with your child restraint to see if
there is enough room to secure your seat properly.
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