Dear Tom and Ray:

I am aware that, while driving in winter conditions, it is important to keep extra weight in the trunk of a car to help with traction. However, now that I have a car with front-wheel drive, this practice seems to be a waste of time. Should I bother putting sandbags in the trunk or not? - DavidTOM: Good question, David. Traction is a complicated issue, and we'll do our best to try to complicate it a little more. The truth is there are three situations in which traction is important: when you're starting, when you're stopping and when you're moving. Other than that, traction doesn't matter.

RAY: Traction is actually a function of a lot of things: the weather, the condition of the road, the tire tread, the car's suspension and the weight of the car, to name just a few. STARTING traction is most affected by the weight directly over the driven wheels. That's why some people put sandbags in the trunk of their REAR-wheel-drive cars.

TOM: And you're right, David. Sandbags aren't necessary for FRONT-wheel-drive cars. Those cars already have the weight of the engine and transmission over the front wheels.

RAY: But there's an even better reason not to fool with sandbags. Your car's handling has been very carefully engineered. When you add weight to one end or the other, you disrupt that delicate balance. In other words, if you throw sandbags in the trunk of a front-wheel-drive car, you tilt the front end up, in effect, taking weight OFF the front wheels. Not only do you reduce your starting traction, but by throwing off the balance, you could easily mess up your braking and handling traction too.

TOM: So while extra weight generally improves traction, the only safe place to put it is in between the wheels. That's why, for traction, we suggest car pooling. In fact, when recruiting car poolers, you could start by putting up a sign at Weight Watchers.

RAY: Actually, David, when it comes to winter traction, there's no substitute for four good snow tires. You should throw one bag of sand in the trunk, but not for the added weight. Carry it so when you DO get stuck, you'll be able to sprinkle some sand under the tires and perhaps get free. If not, at least your kids will be able to amuse themselves by building sand castles while you're waiting for the tow truck.

Dear Tom and Ray:

I enjoy your articles about cars, convertibles in particular. I am the original owner of a 1975 Chevrolet Caprice convertible in excellent condition. It has a big engine and only 38,000 miles. The car is always garaged, and I expect to keep it until 1995. In your opinion, what would the market value of the car be by 1995? - Helen

TOM: Enclosed is $50 in cash, Helen. Just leave the keys under the mat.

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