So I took a nice road trip this past weekend, beautiful weather, etc. I look down at my gas gauge while I'm cruising down the highway, and it's pretty darn close to being on empty. So I freak out a little because I don't want to run out of gas, obviously. I finally come across a gas station, pull in, and fill her up. It only took 12 gallons to fill it up. That means about 7 gallons were still in the tank. The gas gauge definitely gave me the impression it probably only had 2 gallons tops in there. Is this a known issue?