Dear Tom and Ray:

Do those clamp-on or strap-on devices that go on your tires help with winter driving traction? Or do they just clamp on my wallet?

-- James

TOM: Sure, they can help. There are several different types of devices that can be used as temporary traction aids.

RAY: Consumer Reports tested a few of them, and the conclusion was that they can help, under certain situations, but they're not very easy to put on.

TOM: They tested one product called the AutoSock, which is a mesh sock that you slip over each tire, and the mesh gives you additional traction in certain conditions.

RAY: They tested it on a snow-covered hill in Vermont and found that with the AutoSock, they could get their Honda Accord to the top of the hill, which they couldn't do with just the all-season tires.

TOM: They also tested a set of temporary "tire chain-like" things called SnoBootz. With straps and Velcro, you attach these textured rubber pads to your tires, and the pads are supposed to dig into the snow and increase your grip.

RAY: Consumers found that in soft snow, SnoBootz were disappointing. They dug into the snow and got stuck, just like regular tires do. But on roads with packed snow, the SnoBootz were impressive and increased tire grip significantly.

TOM: The downside of these devices is that they're fairly expensive (the AutoSock is 100 bucks per pair of wheels, and the SnoBootz are $250 for four). While that's not quite equal to the price of four good snow tires (which will help you more than anything), it is a significant investment.

RAY: They're also both fairly difficult to install. So you should plan to get wet and cold when doing so.

TOM: And these are not things you can put on in the fall and take off in the spring. They're temporary devices designed for low-speed, short-distance driving. Then they have to be removed.

RAY: There are other products and devices out there that we're less familiar with, but if you've used any temporary traction devices -- successfully or unsuccessfully -- we invite you to tell us, and our other readers, about your experience. Make a note of the name of the product, and leave your comments at www.cartalk.com/snow.

TOM: And if you decide to toss one of these products in your trunk, consider also tossing in a waterproof jumpsuit and some hand-warmers.