I filled up two days ago and everything seemed fine, then when I was coming home from work monday I realized I had already gone through a 1/4 tank, this morning I dropped down to almost 1/2 on my way to work, about 13 miles.
My first thought was that someone was stealing gas, but I stayed at my girls place last night and was at mine before that, also I watched it go down all the way to work. I've been getting mid to high 14 mpg since I've owned the truck, about a year. Now itís around the 7.5-8mpgs so a HUGE decrease.
It's not the tires or winter gas, there has been little fluctuation since I put the tires on and the onset of winter gas, if it was either of those it would have happened long ago, I have done nothing to the truck in the last month or two. I have in the last six months changed the motor oil, diff oil, greased the joints, new air filter, cleaned the MAF and throttle body and replaced the spark plugs with ones form the dealer. I have no codes or pending codes. Not towing anything, nothing has changed in the last month or few days.
Any ideas? I've found a few suggestions around the web but mostly people saying it's winter gas or large aggressive tires, which is not the case since it hasn't been an issue for quite some time and suddenly dropped to almost half.