Where did all these high-mileage cars come from all of a sudden?
It seems you can't watch TV, surf the Internet or pick up a newspaper without seeing an advertisement from an auto manufacturer touting a vehicle that gets 25 to 30 miles per gallon or more.
If all these thrifty and, by extension, environmentally friendly vehicles are out there, why didn't we know about it before now?
The truth, as always, is in the fine print.
General Motors is shouting the loudest about this, boasting that it sells more vehicles that get 30 miles per gallon or more than Toyota or Honda.
How can that be? In these times of high gas prices, General Motors is being kicked hard by the Japanese imports, which consumers perceive as being more fuel-efficient.
The answer is that GM is citing Environmental Protection Agency figures that relate strictly to highway driving.
Of course, your real-world driving will differ -- perhaps greatly.
The EPA highway test has the vehicle run at speeds as high as 80 mph, with an average of about 50 mph. That's good as far as it goes, but most drivers rarely average much above 35 mph in their daily routine, and much of that is in stop-and-go driving.
That means someone who buys a car based on the higher highway mileage claim will likely be disappointed because they will be unable to achieve that sort of economy overall.
GM is not the only manufacturer touting just the EPA highway fuel economy numbers. Toyota, Ford, Chrysler and almost every other manufacturer are trying to entice buyers with the highest possible ratings.
The claims are truthful as far as they go, but buyers should beware.
A good rule of thumb is to assume that a vehicle will deliver day-in, day-out, mileage that's about 10 percent higher than the city EPA rating.
Mileage will still vary from time to time.
If you're in constant gridlock in midtown Manhattan, expect miserable fuel mileage on all but hybrid vehicles, which will shut down the gas engine when the car is stopped or moving slowly.
If you're on a wide-open highway in Kansas -- and can keep your speed to 55 mph -- you'll likely get mileage above the EPA highway number, especially if you use the cruise control.
The lesson for buyers is that information about fuel economy needs to be filtered with the knowledge that you can't expect to always -- or maybe ever -- get the greatest fuel economy touted on the window sticker or in advertisements.
That doesn't mean a buyer shouldn't shop for the most fuel-efficient vehicle, if that's important to their budget. Just don't expect miracles.
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