Q Dear Tom and Ray:

Every year when winter rolls around in the tundra we call Northern Illinois, I hear the same old advice: that we should all keep our gas tanks at least half full to prevent gas-line freeze. No one has ever been able to tell me how a car with a quarter-tank of gas is more apt to experience gas-line freeze than a car with a half-tank. If keeping half a tank is good, is keeping three-quarters of a tank better?

-- John

A RAY: Gas-line freezing was more of a problem in the old days, when pterodactyls chased my brother home from school and gas tanks were vented directly to the atmosphere through a hole in the gas cap.

TOM: So when you had only a small amount of gas in the tank, the rest of the space would be filled with air. And if it happened to be damp out, there could be lots of moisture in that air. And if the temperature dropped, that moisture could condense, and you'd have water in the gas.

RAY: Then, if that water flowed through the gas lines and the temperature dropped again, the water could freeze and prevent the engine from running.

TOM: So keeping more gas in the tank was really just an easy way of keeping the air out. Therefore, the answer to your question (at least in the old days) was yes. Three-quarters of a tank was better than half a tank. And a full tank was best of all. We used to tell our customers the best way to prevent a freeze-up is to fill the tank. And then don't drive anywhere all winter!

RAY: We almost never see gas lines freezing these days. It might be because of better winter gasoline formulations, or because of the way gas tanks are now vented through a charcoal canister. But whatever the reason, it's an increasingly rare phenomenon in most places.

TOM: Nonetheless, we still recommend keeping your tank at least half full in the winter, but not for the reason you think. If you get stuck in the snow, you'll be able to keep the engine running, which is crucial.

I have a 1994 Ford Thunderbird LX with a V-8 and only 29,000 miles on it. I keep seeing people pull in and out of parking spaces using only one hand on the steering wheel. I have to use two hands to move the wheel while the car is either stopped or moving slowly. I am over 6 feet tall and weigh 190 pounds, and I have never owned a car that had a steering problem like this. I have taken the car to the dealer at least 10 times for routine maintenance. Each time, the mechanic says the steering is okay. I keep telling him I watch "Cops" on television and they're always driving their Fords with one hand, so why is my wheel so hard to turn?

-- Carl

TOM: Well, now you know why cops don't drive '94 Thunderbirds. They can't steer them with one hand and balance their doughnut and coffee in the other.

RAY: Even though the dealer says nothing is wrong, I'm going to guess that your power-steering pump is bad. Usually, power-steering pumps whine or groan when something's wrong. And that's probably what the dealer was looking for. But sometimes they don't make noise when they start to fail, and instead they just slip gently into that good night.

TOM: A big guy like you shouldn't need both hands to turn the wheel, so I'd ask the dealer to try changing the power-steering pump for you and see if that fixes it.

RAY: If it doesn't, then I suppose it could be a design issue. You should ask the dealer if there's another '94 T-Bird you can drive and then see if it does the same thing.

TOM: But I'd put my money on a bad pump. And since this is cutting into your enjoyment of cop shows on television, I'd ask the dealership to change the pump for you, even though the old one sounds fine.

Got a question about cars? Write to Click & Clack in care of The Post or e-mail them through the Car Talk section of the Cars.com Web site.

(c)2002 by Tom and Ray Magliozzi

and Doug Berman