Dear Car Talk:
I bought a used 2008 Ford F-150 about three years ago. It's an excellent vehicle and very trouble-free, except for regular maintenance of course.
The only irritating issue is low fuel economy. I bought a cover for the bed and that improved the mileage, but it still gives me only 16-18 mpg.
Any suggestions for better miles per gallon? Thanks. — Frank
Yeah, a Toyota Prius.
If you bought a zebra, you'd expect it to have stripes, right, Frank? Well, you bought a pickup truck, and you should expect it to get mediocre gas mileage. That's baked in.
In fact, 16-18 mpg sounds pretty good to me. The EPA rating for this truck, back in 2008, was 14 mpg city and 19 highway, with an average of 16 mpg. So, you're already exceeding expectations.
If you had come to our shop and said that you used to get better fuel economy, and it had dropped recently, there are some things we would check.
The first would be your reliability as a witness. But if you survived our cross examination, we might start by checking your tire pressure. Low tire pressure is not only dangerous, but because it creates a bigger patch of rubber on the road, it creates more friction and can also result in lower mileage.
We'd also check your thermostat. If your thermostat were stuck halfway open or opening too early, your engine might not be getting all the way up to operating temperature. And an engine running cool will run inefficiently, with lower mileage.
We might check for an obstructed exhaust too. If your engine wasn't breathing properly, that could lead to wasted fuel.
Finally, if it's an old vehicle, we might check the compression, because an engine that's not fully compressing its fuel-air mixture is obviously not getting the most out of each drop of gas.
In your case, I really doubt you've got any problem at all, Frank.
If you really want to see if you can improve your mileage any further, you might want to try overinflating your tires by a few pounds more than the recommended pressure. Just be sure to stay below the tire manufacturer's maximum pressure.
Also, you can make sure your truck is empty when you're not actively hauling anything. Extra weight will decrease mileage. And you can drive slower. The difference in fuel economy between going 75-80 mph versus 55-60 mph is enormous. If it matters that much to you, slow down.
But don't expect any miracles, Frank. You're already at the winning end of the F-150 fuel economy bell curve.