Buick RIVIERA 1993 Manual page 215

Don't use your compact spare on some other vehicle.
And
don't mix^ your compact spare or wheel with other
wheels or tires. They won't fit. Keep your spare
and
its
wheel together.
A
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.
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