Starting And Operating Your Vehicle; New Vehicle Break-In; Ignition Positions - GMC Yukon Denali 2003 Owner's Manual

Starting and Operating Your
Vehicle

New Vehicle Break-In

Notice: Your vehicle doesn't 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).
•
Don't drive at any one speed — fast or
slow — for the first 500 miles (805 km). Don't
make full-throttle starts.
•
Avoid making hard stops for the first 200 miles
(322 km) or so. During this time your new
brake linings aren't 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.
•
Don't tow a trailer during break-in. See "Towing
a Trailer" in the Index for more information.
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Ignition Positions

With your key in the ignition switch you can turn it to
four different positions.
A (LOCK): This position locks your ignition and
transmission. It's a theft-deterrent feature. You will only
be able to remove your key when the ignition is
turned to LOCK.