GMC 1996 Sierra Owner's Manual page 88

NOTICE:
Driving with the parking brake on can cause
your rear brakes to overheat. You may have
to replace them, and you could also damage
other parts of your vehicle. Always check to be
sure your parking brake is fully released before
you drive.
If you are towing a trailer and are parking on any hill,
see "Towing a Trailer" in the Index. That section shows
what to do first to keep the trailer from moving.
If you have a 3500 HD model,
it
is
recommended that
the propshaft mounted parking brake be burnished as
part of the new vehicle break-in. The parking brake will
work best after it has been burnished following these
instructions.
Make 10 stops, using the parking brake foot pedal, from
20 mph
(32 km/h) about 2 1/2 miles (4 km) apart. In
between stops, drive the vehicle at 20 mph (32 km/h).
Shifting Into PARK (P) (Automatic
Trawrission Models Only)
It can be 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.
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, use
the steps that follow. If you have four-wheel
drive and your transfer case is
in NEUTRAL (N)?
your vehicle will be free to roll, even if your shift
lever is in PARK (P). So, be sure the transfer case
is in a drive gear
--
not in NEUTRAL (N). If
you're pulling a trailer, see "Towing a Trailer''
in the Index.
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