Q: My husband has this 6,000 pound Ranger Fishing boat that he needs to tow. Do you know of a fuel-efficient, not-too- big car to pull it? My kids would kill him if he bought an SUV. Also, it should be used and not too expensive. I was thinking along the lines of something like a Subaru? -Thanks, Mary D., Minneapolis

A: Better start working on the kids. A smaller, inexpensive, fuel-efficient vehicle capable of pulling that boat is a tall order. Maybe too tall.

It's not until you dig into it that you realize there's more than logic and perception to towing. We've all known smaller people who were quite strong for their size. They might be able to move a TV or load a truck with firewood just as quickly and easily as someone bigger. We've all seen pro running backs below 200 pounds, some below 180 or 170. If these players can mix it up with guys much bigger, can't small vehicles do the work of big ones?

Gasoline engines are powerful, rubber tires have incredible grip and Subarus are all-wheel drive. Can't they tow a boat the same way these strongest-man-competition guys pull train cars and move huge stones? The real question is, can they do it safely, without undue risk of crashing or breaking? As the object to be towed becomes sizeable, the answer, unfortunately, is no.

As cool and competent as Subarus are (if the money train stops by my house, my wife and I are buying WRXs and going to rally-driving school), Outbacks are tow-rated for a maximum 2,700 pounds (Foresters for 2,400). That means trailer plus boat plus gas, battery, anchor and anything else on the trailer can't total more than 2,700 pounds. Ranger boats weigh more.

If your husband's boat is a 600 series, for example, the current 618T has a trailer gross vehicle weight rating of 3,725. For the 620 and 621 models, this figure jumps to 5,000 pounds. Could a Subaru Outback move this trailer? In an emergency, if someone's leg were pinned under it, sure, the Outback could pull the boat off. But by setting the tow limit well below this number, Subaru is saying it is not safe to pull something this size over the road with that vehicle. The engine, suspension, transmission, differentials, brakes, etc., would be over-stressed hauling this load.

Trailers exert a tongue weight downward on the hitch. Suspension movements and weight imbalances can also cause the trailer to sway, like a pendulum, behind the tow vehicle - because the trailer, like the car, exerts forces on the hitch. If the trailer is heavy and the tow vehicle is light and has a short wheelbase (long wheelbases resist sway more), a trailer can disconnect or even throw the tow vehicle out of control. A few years ago, someone towing a heavy trailer with a short wheelbase SUV on one of our highways lost control and crossed into oncoming traffic, causing a head-on collision.

You husband's best bet for something inexpensive and up to the task is probably an older full-size pickup truck with a tow package. It will have the power, wheelbase and stiffer suspension to pull the boat and resist sway. A load-leveling (or distributing) hitch will pull a heavier trailer with more control. If the whole family needs to fit in the vehicle, check out extended cabs and four-door trucks.

Sorry this isn't a fuel-efficient solution. Check the six-cylinder tow ratings for a little more miles per gallon. On the plus side, if gas hits $4 a gallon, you might be able to save on the truck's purchase price some of what you lose at the pump.

Send automotive-related questions to: weekendgarage@comcast.net