I drive 2007 dodge nitro, sxt 2wd 3.7L with one kinda low driver front tire, and I am getting horrible mpg. I am normal Russian driver, live in Texas, so speed limits go up to 70 in my area. I usually get 19-21mpg, but lately, my gas gauge will move like 5-6 gallons in only 60-65 miles!!! This is not right, not even with a kinda low tire, please, any help on how to save would be much appreciated.