Wife primarily drives our 2006 GMC Envoy. It has 136,000 miles. New thermostat August 2012. New Battery October 2012. Cut off this past Saturday, while backing out of Garage. I thought I smelled antifreeze, but when wife returned home could not smell. Drove 30 miles or so on Sunday with no apparent problems. She called me today to advise that it almost would not restart after driving 15 miles and dropping daughter to summer day care. Ask her to keep an eye on gauge for charging system, try to notice how it is reading with/without ac on, using pwr windows, etc. She has not reported any more problems today. Is our alternator about to leave her stranded?