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.
See also:
How to Check Power Steering Fluid
Notice: Extremely small amounts of contamination can cause steering system damage and cause it to not work properly. Do not allow contaminants to contact the fluid side of the reservoir cap/ dipstick ...
Headlamp Aiming
Headlamp aim has been preset and should need no further adjustment.
If the vehicle is damaged in a crash, the headlamp aim may be affected.
If adjustment to the headlamps is necessary, see your deal ...
Interior
The Sierra showcases two different interior designs. Work Truck and SLE
models are more utility-minded, with large controls and door handles that can be
operated while wearing gloves. The SLT offe ...