There are miles per gallon... and then there are miles per gallon. How do you tell the difference? One is labeled "CAFE mpg" and the other is labeled "EPA mpg." What's the difference? Well, Edmunds is taking pains to illuminate the large discrepancy that exists between the two figures: the issue, as initially laid out by Edmunds' John O'Dell in 2007, is that CAFE and EPA mileage numbers were initially based on the same formula in 1975. When consumers complained that the number didn't correspond to real-world gas mileage, the EPA determination formula was changed – twice – yet the CAFE formula wasn't.
The change meant that when a customer bought a car that listed 26 combined mpg (EPA) on the window sticker, the CAFE mpg rating for that car remained at around 35 mpg. And if you've been paying attention to the myriad CAFE stories over the past year, you'll know that the government is tweaking CAFE numbers, not EPA numbers. The NHTSA oversees CAFE numbers, the EPA keeps track of "vehicle fuel efficiency."
But the gap between the two sets of computations means, according to Edmunds:
"a vehicle that scores an EPA combined rating of 29 miles per gallon actually contributes 39 MPG to its manufacturer's CAFE average. There are 29 car models and 36 truck models that already achieve the new standard, and about a third of the cars and half of the trucks are produced by a domestic automaker."
Ultimately, it means that the formerly punitive mpg numbers that the government mandated can now be considered for what they really are: Meh.
[Autoblog]
