GMC 2003 Sierra - Manual (Page 165)

Cruise Control This can really help on tong trips. Cruise control does
noi work at speeds below about 25 mph [40 km/h).
It you apply your brakes, or press Ihe dutch pedal (rf
equipped), the cruise conlrol will disengage.
O* Off
I ; On
+ t Resume/Acceleraie
: Set
With cruise controlf you can maintain a speed of about
2S mph (40 km/h) or more wllhout keeping your foni
on the accelerator.
^
CAUTION:
Cruise control can he dangerous where
you can't diive safely at a steady speed.
SOi don't use your cruise control on
wlrtdir^g roads or In heavy traffic.
Crufse Control can be dangerous or>
slippery roads. On such roads, fast
changes In tire traction can cause
needless wheel spinning, and you could
lose control. Don't use cruise conlrol on
slippery roads.
3‘10