See also:

Using the “Re-dial” Command
1. Press and hold for two seconds. 2. After the tone, say “Re-dial.” Once connected, the person called will be heard through the audio speakers. ...

New for 2010
GM has dropped the long-running 6.0-liter V-8 engine from the Sierra lineup, leaving the powerful 6.2-liter V-8 for heavy towing needs. The rest of the Sierra's eight-cylinder lineup benefits from ...

How the System Works
URPA comes on automatically when the shift lever is moved into R (Reverse). A single tone sounds to indicate the system is working. URPA operates only at speeds less than 8 km/h (5 mph). An obstac ...