GMC Sierra 2500 HD 2024 Owner's Manual page 247

Reducing Speed While ACC Is at a Set Speed
If ACC is already activated, do one of the
following:
Use the brake to get to the desired lower
speed. Release the brake and press SET .
The vehicle will now cruise at the lower
speed.
Press and hold SET until the desired
lower speed is reached, then release it.
To decrease the vehicle speed in smaller
increments, press SET briefly. For each
press, the vehicle goes about 1 km/h
(1 mph) slower.
To decrease the vehicle speed in larger
increments, hold SET . While holding
SET , the vehicle speed decreases to the
next 5 km/h (5 mph) step, then continues
to decrease by 5 km/h (5 mph) at a time.
The set speed can also be decreased while
the vehicle is stopped.
If stopped with the brake applied, press
or hold SET until the desired set speed is
displayed.
Selecting the Follow Distance Gap
When a slower moving vehicle is detected
ahead within the selected following gap,
ACC will adjust the vehicle's speed and
attempt to maintain the follow distance gap
selected.
Press on the steering wheel to adjust
the following gap. Each press cycles the gap
button through three settings: Far, Medium,
or Near.
When pressed, the current gap setting
displays briefly on the instrument cluster
and HUD, if equipped. The gap setting will
be maintained until it is changed.
Far Gap Setting
Driving and Operating
Medium Gap Setting
Near Gap Setting
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