Hello, I'm sure it's been covered, but in a quick search I can't find the answer I'm looking for. I've got a 3.7 Liberty with the auto trans and in about a year of owning, haven't gotten above 15mpg more than a couple times and those only on road trips. I've changed, spark plugs, air filter, O2 sensors, and all fluids. What else can be a cause of mileage issues? I know these aren't overly efficient but consistently getting between 14.5-15mpg seems a bit off.