The difference in annual fuel costs between 24 and 21 mpg at current prices and 15K miles a year is 60 cents a day.
Which is why I don't bother checking
I put about 7k miles on the truck per year. If I got 20 MPG, that would be 350 gallons. If I got 15 MPG that would be 467 gallons. That's a huge jump in MPG, yet we're talking about $200-250 per year in that 5 MPG range. If I can't find 20 bucks a month to not have to worry myself to death about fuel economy I really need a different vehicle. I remember back in 05-07 when gas prices jumped way up there and all the guys on the Titan forum were dumping their trucks - many of them at a loss - and buying Corollas and stuff like that. I tried showing them on spreadsheets that it made zero sense to take a loss on the vehicle just to get better gas mileage, since it would take a boatload of driving to make up the loss, but you just couldn't speak math to some of these guys. There were guys looking at taking $5-10k hits to buy cheaper vehicles to save $1k in gas per year, and that's when gas was $4.
Like everything, half of life is just showing up with the right tool for the right job. If you drive 30k miles a year by yourself on paved highways and don't haul anything more than a cooler you probably got the wrong tool for the job, unless you just have money to burn in which case have at it
