I was feeling really good about getting 27.9mpg with my minvan with a 3.8 V6.
Then I changed my oil to a thinner synthetic, pumped up my tires to the max, installed a grill block, and sat back waiting for those mpg points to start rolling in. Instead I've been getting more like 26.6.
I was kind of disappointed till I found this in aeroheads album:
Since it's been colder than 20F for a while, and I drive around between 5280 and 11,300 in elevation, I started feeling a bit better about it.
Someone somewhere said, "Can't do anything about the weather."