do some research on the forums and google... understand what it means to use higher octane versus lower...

a quick paraphrase: low/mid/high/premium/etc... those mean jack squat to what the gas actually is

 

Also make sure you have your tires properly inflated. Stock tire sizes should be around 35-40 psi to help achieve optimum fuel economy.

I haven't dealt with low profile tires or bigger tires around 225, but I'd assume the same would apply to those as well.

 

I get about 28-29 mpg on city on average 40-50 mph, and 35 mpg(70-75 mph highway)or more if i go to 65-70 mph. I use to get less on both till i found out i had a front end alignment issue(toe-in) it was wearing my front tires pretty good. since then it 's been great! wish the gas price would go down more though....