I have a 2008 titan 4x4 love the truck and runs great. I have been checking my miles per gallon a lot. With 87 octane i have been getting around 15.8 in town but here is the kicker when i run 93 i might get 12.9 at the most 13.5 what the h*ll. I was talking to two other guys local with the same truck getting 19 in town on 93 octane. So is there something wrong or what.