An engineer with the EPA’s fuel-economy team says, not unreasonably:
“Everybody wants a label that tells you exactly what you’re going to get, but obviously that’s not possible. A good general rule of thumb is that real-world fuel economy is about 20 percent lower than the lab numbers.”
This despite the 2008 fudge factors, which lowered the existing estimates by 10-20 percent. For instance, see this sample, with which I am rather familiar. Contributors are claiming that they’re beating not only the new, lower numbers, but the old, higher numbers as well. Which I believe, since I’m beating them myself.
So why is “real-world” fuel economy higher on this model than on so many others? I continue to believe that the X factor here is whether or not the automaker tried to build to the test, to produce a vehicle that would do well on the test and let the real world go hang.
If I’m asked, I will happily quote this EPA guy. And I will remind the asker that nine times out of ten, the ads are quoting the somewhat-nebulous highway figure, which you will never, ever achieve on your way to work.