Pontiac 1993 Grand Am Owner's Manual page 91

Speedometer and Odometer
Your speedometer lets you see your
speed in both miles per hour (mph) and
kilometers per hour (kmlh). Your
odometer shows how
far
your vehicle
has been driven, in either miles (used in
the U.S.) or kilometers (used in
Canada).
Tamper Resistant Odometer
Your hntiac has a tamper resistant
odometer. If you see silver lines
between the numbers, you'll know that
someone has probably tried to turn it
back, so the numbers may not be true.
You may wonder what happens if your
vehicle needs a new odometer installed.
If the new one can be set to the mileage
total of the old odometer, then it must
be. But if it can't, then it's set at zero
and a label must be put on the driver's
door to show the old mileage reading
when the new odometer was installed.
Trip Odometer
The trip odometer can tell you how far
you have driven since you last reset it.
To reset the trip odometer to zero, press
the
knob to the right of the gage.