Starting And Operating Your Vehicle; New Vehicle Break-In; Ignition Positions - GMC Sierra Denali 2009 Owner's Manual

Starting and Operating Your
Vehicle

New Vehicle Break-In

Notice: The vehicle does not need an elaborate
break-in. But it will perform better in the long run if
you follow these guidelines:
•
Keep your speed at 55 mph (88 km/h) or less for
the first 500 miles (805 km).
•
Do not drive at any one constant speed, fast or
slow, for the first 500 miles (805 km). Do not
make full-throttle starts. Avoid downshifting to
brake or slow the vehicle.
•
Avoid making hard stops for the first 200 miles
(322 km) or so. During this time the new brake
linings are not yet broken in. Hard stops
with new linings can mean premature wear and
earlier replacement. Follow this breaking-in
guideline every time you get new brake linings.
•
Do not tow a trailer during break-in. See Towing
a Trailer on page 4-43 for the trailer towing
capabilities of the vehicle and more information.
Following break-in, engine speed and load can
be gradually increased.

Ignition Positions

To shift out of P (Park), the ignition must be in ON/RUN
or ACC/ACCESSORY and the regular brake pedal
must be applied.
The ignition switch has
four different positions.
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