I was averaging around 300 miles to a tank (15mpg) pretty much since I got the truck. Last week, I hit 362 miles before the fuel light came on. I was tempted to push it to see if I could get 19mpg, but due to other circumstances, it was deemed wise not to do that *lol*. Regardless, I was pretty pleased to see it happen. My truck is completely stock engine-wise. I haven't even changed the plugs since I bought it in Sept. of last year. The only thing I did before the mileage change was finally change the oil, and I went to my preferred brand, Royal Purple. Now, I'm not saying the RP change can be contributed to the mileage increase, but the before and after is a pretty strong indication that it had something to do with it.

On my 2nd fill up, I'm @ 125 miles and have gone through ~1/3 of a tank. Hopefully this is here to stay. I plan on changing the air filter and spark plugs in June, and today I'm installing an electric fan. At some point, I'd like to see 20mpg, even if it happens once.