Chevrolet 2000 Impala Owner's Manual page 89

The above graphic is also displayed on your instrument
panel cluster.
Maximum engine speed is limited on automatic
transaxle vehicles when you're in PARK (P) or
NEUTRAL (N) to protect driveline components from
improper operation.
There are several different positions for your shift lever.
PARK (P): This locks your front wheels. It's the best
position to use when you start your engine because your
vehicle can't move easily.
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CAUTION:
It is dangerous to get out of your vehicle if the
shift lever is not fully in PARK (P) with the
parking brake firmly set. Your vehicle can roll.
Don't leave your vehicle when the engine is
running unless you have to. If you have left the
engine running, the vehicle can move suddenly.
You or others could be injured. To be sure your
vehicle won't move, even when you're on fairly
level ground, always set your parking brake and
move the shift lever to PARK (P).
See "Shifting Into PARK (P)" in the Index. If
you're pulling a trailer, see "Towing a Trailer" in
the Index.
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