GMC 2005 Canyon Owner's Manual page 388

Parking Brake and Automatic
Transmission Park (P) Mechanism Check
CAUTION:
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When you are doing this check, your vehicle
could begin to move. You or others could be
injured and property could be damaged.
Make sure there is room in front of your
vehicle in case it begins to roll. Be ready to
apply the regular brake at once should the
vehicle begin to move.
6-12
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 transmission in
NEUTRAL (N), slowly remove foot pressure from
the regular brake pedal. Do this until the vehicle is
held by the parking brake only.
•
To check the PARK (P) mechanism's holding ability:
With the engine running, shift to PARK (P).
Then release the parking brake followed by the
regular brake.
Contact your GM Goodwrench dealer if service is
required.
Underbody Flushing Service
At least every spring, use plain water to flush any
corrosive materials from the underbody. Take care to
clean thoroughly any areas where mud and other debris
can collect.