GMC 2003 Safari Owner's Manual page 136

Resuming a Set
Speed Increasing Speed While Using Cruise
Suppose you set your cruise control at a desired speed
Control
and then you apply the brake. This, of course, shuts There are two ways to go to a higher speed:
off the cruise control. But you don't need to reset it.
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Use the accelerator pedal to get to the higher
Once you're going about
25 mph (40 km/h) or
more, you can move the
cruise control switch
from ON to R/A
(Resume/Acclerate) briefly.
You'll go right back up to your chosen speed and
stay there.
If you hold the switch at R/A, 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 R/A.
speed. Press the button at the end of the lever,
then release the button and the accelerator pedal.
You'll now cruise at the higher speed.
Move the cruise switch from ON to R/A. Hold it
there until you get up to the speed you want,
and then release the switch. To increase your
speed in very small amounts, move the switch to
R/A briefly. Each time you do this, your vehicle will
go about 1 mph (1.6 km/h) faster.
Reducing Speed While Using Cruise
Control
There are two ways to reduce your speed while using
cruise control:
0
Press the button at the end of the lever until you
reach the lower speed you want, then release it.
0
To slow down in very small amounts, press the
button briefly. Each time you do this, you'll go
about 1 mph (1.6 km/h) slower.
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