GMC 2009 Sierra - Manual (Page 98)

Starting and Operating Your
Vehicle
New Vehicle Break-In
Notice: Your 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 4-41 for the trailer towing
capabilities of your vehicle and more
information.
Following break-in, engine speed and load can be
gradually increased.
Ignition Positions
Use the key to turn the
ignition switch to four
different positions.
In order to shift out of PARK (P), ignition must be in the
ON/RUN or ACC/ACCESSORY and the regular brake
pedal must be applied.
A (LOCK/OFF): This position locks the ignition and
transmission. It is a theft-deterrent feature. The key can
only be removed when the ignition is turned to
LOCK/OFF.
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