GMC Sierra Denali Classic 2007 Owner's Manual page 150

Setting Cruise Control
CAUTION:
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If you leave your cruise control on when
you are not using cruise, you might hit a
button and go into cruise when you do not
want to. You could be startled and even
lose control. Keep the cruise control switch
off until you want to use cruise control.
1. Move the cruise control switch to on.
2. Get up to the speed you want.
3. Press in the set button at the end of the lever
and release it.
4. Take your foot off the accelerator pedal.
150
The cruise symbol on
the instrument panel will
illuminate when the
cruise control is
engaged.
Resuming a Set Speed
Suppose you set your cruise control at a desired
speed and then you apply the brake. This, of
course, disengages the cruise control. But
you don't need to reset it.
Once you're going about 25 mph (40 km/h) or
more, you can move the cruise control switch
briefly from on to resume/accelerate.
You'll go right back up to your chosen speed and
stay there.
If you hold the switch at resume/accelerate the
vehicle will keep going faster until you release the
switch or apply the brake. So unless you want
to go faster, don't hold the switch at resume/
accelerate.