Myth of the Little SUV Debunked

Hey Mr. Green,
I was very disappointed in your answer to the recent question about whether cars get lower gas mileage because of safety or antipollution devices. Your answer was these devices do not add weight to cars or reduce mileage. What are you talking about? At least admit that pollution-control devices like the catalytic converter impair good mileage.

I had a '90s Subaru Loyale that got more than 35 miles to the gallon, even after it was eight years old! My new Honda CRV, which I admit is a little bigger, can hardly get 22 miles per gallon, and I consider myself a good driver! –Carl in Bannockburn, United Kingdom

Hey Carl,
Your comparison actually proves my point about auto companies' stupid, inefficient giantism. Your Honda is more than a "little bigger" than the Subaru: It's a whopping one-third bigger. The Honda CRV weighs a half ton more and has at least 50 more horsepower. The CRV has a curb weight of about 3,500 pounds and a horsepower of 166, whereas the old Loyale wagon had a curb weight of around 2,400 and a horsepower of 90 or 115, depending on the type of engine. The difference in gas mileage is a result of that extra heft and oomph.

(Note: I call giantism "stupid" because Detroit is now in the same mess it was in 35 years ago. That's when car sales plunged because it had no efficient vehicles to offer during the gas crunch. You'd think that the old boys who run GM and Ford would have some recollection of this disastrous event.)

The CRV is only an inch or so longer, but it's half a foot wider and more than a foot higher. Talk about safety adding to a vehicle's size and weight? Well, one of the biggest safety problems with SUVs is precisely because they're taller, with a higher center of gravity that causes them to flip over more easily. Though the CRV is one of the more efficient SUVs (Click and Clack approve of it), it's still a product of  carmakers' push for size and power and U.S. consumers' infatuation with the same.

As for antipollution controls diminishing efficiency, the opposite is true. The more efficient a car is, the less it pollutes. In the 1970s, when cars were only getting around 13 miles per gallon, they were pumping a lot more gunk into the air than today. Regarding catalytic converters, they've been standard equipment since the mid-'70s. You can't blame them for the CRV-Loyale mileage gap because your Subaru had one too [PDF]. As far as I know, a catalytic converter doesn't affect gas mileage unless the converter is clogged and blocks the exhaust flow. This can happen, but is a maintenance issue not inherent to the converter itself.

You are obviously a good driver, since you are getting about what the EPA rates CRV at: 23 mpg combined city and highway, with 20 in the city and 27 on the road. The Loyale was rated at 21 in the city and 26 on the road, so you actually beat the ratings with your old car. But even the best driving in the world can't defy the laws of physics.