GMC 2010 Sierra 1500 Crew Cab Owner's Manual page 231

In freezing weather, do not use your washer until
the windshield is warmed. Otherwise the washer
fluid can form ice on the windshield, blocking your
vision.
Push the paddle marked with the
windshield washer symbol at the top of the multifunction
lever, to spray washer fluid on the windshield. The
wipers clear the window and then either stop or return
to the preset speed.
Cruise control can be dangerous where you
cannot drive safely at a steady speed. So, do not
use the cruise control on winding roads or in
heavy traffic.
Cruise control can be dangerous on slippery
roads. On such roads, fast changes in tire traction
can cause excessive wheel slip, and you could
lose control. Do not use cruise control on slippery
roads.
For vehicles with cruise control, a speed of about
40 km/h (25 mph) or more can be maintained without
keeping your foot on the accelerator. Cruise control
does not work at speeds below about 40 km/h (25 mph).
When the brakes are applied, cruise control is
turned off.
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