Pontiac 2002 Aztek Owner's Manual page 324

Storing a Flat or Spare Tire and Tools
CAUTION:
Storing a jack, a tire or other equipment in the
passenger compartment of the vehicle could
cause injury. In a sudden stop or collision, loose
equipment could strike someone. Store all these
in the proper place.
CAUTION:
-
The underbody mounted spare tire needs to be
stored with the valve stem pointing down. If the
spare tire is stored with its valve stem pointing
upwards, its secondary latch won't work
properly, and the spare tire could loosen and
suddenly fall from your vehicle. If this happened
when your vehicle was being driven, the tire
might contact a person or another vehicle,
causing injury and, of course, damage to itself as
well. Be sure the underbody
is stored with its valve stem pointing down.
-
mounted spare tire
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