Chevrolet 2011 Express 1500 Cargo Owner's Manual page 306

When you are doing this check,
the vehicle could begin to move.
You or others could be injured
and property could be damaged.
Make sure there is room in front
of the vehicle in case it begins to
roll. Be ready to apply the regular
brake at once should the vehicle
begin to move.
Park on a fairly steep hill, with the
vehicle facing downhill. Keeping
your foot on the regular brake, set
the parking brake.
To check the parking brake's
holding ability: With the engine
running and the transmission in
N (Neutral), slowly remove foot
pressure from the regular brake
pedal. Do this until the vehicle is
held by the parking brake only.
To check the P (Park)
mechanism's holding ability:
With the engine running, shift to
P (Park). Then release the
parking brake followed by the
regular brake.
Contact your dealer if service is
required.
Windshield wiper blades should be
inspected for wear and cracking.
See
for more information on
wiper blade inspection.
Replacement blades come in
different types and are removed in
different ways. To remove the type
with a release clip, do the following:
1. Lift the wiper arm until it locks
into a vertical position.