The numbers in the ads are for highway driving only. The estimate for city driving is less than 30 mpg for most of the cars. So unless you drive mainly on the freeway, you're not going to get 40 mpg.
And you often can't get the best mileage with the base model, something most ads bury in the fleeting fine print.
With the Ford Focus, you'll have to get the SE sedan for more than $17,000 and add a $500 Super Fuel Economy Package.
As for the Chevy Cruze, you'll need to buy the $18,000 Eco version that comes only with manual transmission.
And the Honda Civic HF advertised goes for more than $20,000. That's $5,000 more than the base model.
The Hyundai Elantra is a little different. It promises 40 mpg for its base model, which starts at $15,000. But in Consumer Reports tests the Elantra got 39 mpg on the highway, and 29 for city driving. That's pretty good for the Elantra's class, but it's not quite the promised 40 mpg.
So the next time you hear a commercial touting 40 mpg or more, take it with a grain of salt.
In Consumer Reports mileage tests, there are several cars that do deliver 40 mpg on the highway, or even more. They're the Toyota's Yaris and Corolla, as well as the Mazda3. But remember, that's just for highway driving. Overall mileage will be considerably lower.
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