Thank you all, I am already being educated. I did read the 2014 Silverado's Owners Manual, but stopped when I got to the section that said to not engage 4WD High when on dry pavement, and showed the selector knob with 2WD, 4H, 4L and neutral. Following Bud's lead, I read further on and found the 4WD Auto, and the selector knob that includes Auto. Does indeed sound like what I want. Many thanks again. Now I am really looking forward to the release of the 2015 Tahoe/Yukon.
Does Ford F150/Expedition have the same Auto feature?
Bruce