I bought a new silverado back in sept of 2010. Its the 5.3 flex fuel. Window sticker says 15-21. I'm yet to see anything over 15 mpg. On highway travel I have never gotten over 350 miles on a tank. And with my regular travels I get right around 300 miles on a tank.
I have had it back to the dealing 3 times. They plug it into the computer and say everything is fine. Well if its fine why aren't I getting the MPG's that GM brags about?
I have been in contact with a GM customer service rep for over 2 months. He had me take it to another dealer and I had the same results there. They take it into service and 30 minutes later. I'm done and they say there is nothing wrong with the truck. Where do I go from here?? What can I do?