Tuesday, January 25, 2011

Technology for Winter Driving


By Joe Wiesenfelder, Cars.com

Let's say your looking for a new car. If you've never had to pry a wiper loose from a frozen windshield, you might not recognize the comfort and safety challenges that confront motorists in harsh winter climates. If you live in a colder clime, you do know the horror of losing sensation in your fingers and toes or sliding haplessly into a ditch. Either way, make sure your new car has some of these features to make life in snow country a lot easier.
Antilock Brakes
Antilock braking systems are good for all seasons. They keep your car under control during braking by preventing the wheels from locking and skidding. ABS shortens stopping distances in most cases, but its main purpose is to allow steering, even when you are in a panic stop.

Traction Control
Where antilock brakes help you stop on slippery surfaces, traction control helps you accelerate. It detects when your drive wheels are slipping and reduces engine power and/or applies the ABS to keep power going to the wheel that has traction. While traction control has helped make rear-wheel-drive cars more viable in snow, some systems are so conservative that they keep you from gaining speed on loose snow and may need to be switched off. The most advanced traction control is better at reacting optimally for any given road surface.

Electronic Stability System
Electronic stability systems are known by countless names, usually including the word stability. What they do is sense the car's direction, compare that to where the driver is steering and apply individual ABS brakes to steer the car back on its intended course. One of the most significant auto safety advancements in history, stability control is especially useful in snow, where it can prevent fishtailing. Though expensive, it can pay for itself by preventing a single fender bender.

Four-/All-Wheel Drive
The need for four-wheel drive for urban dwellers is probably overstated these days, but it certainly can't hurt, especially in wintery regions that have hills and/or poor snow removal. Heavy-duty four-wheel drive is often overkill; all-wheel drive, which is lighter and cheaper, is totally automatic and may be more effective.
Ground Clearance
Too many sports-car owners learn too late that all-wheel drive can only do so much in a car that hugs the ground. Throw in a set of summer tires and you're really going nowhere - at least nowhere you want to go. In deeper snow, SUVs and higher-riding sport wagons rule the road.

All-Season or Winter Tires
The importance of tires can't be overstated, especially in winter conditions. While modern "winter" (no longer "snow") tires are exceptional on snow and particularly ice, they may suffer from extended stopping distances and diminished traction when it's dry or warm. Good all-season tires are an excellent compromise for people who don't need - or can't justify - a second set of tires and the hassle and expense of storing and swapping them twice a year. That said, don't use summer performance tires in the snow. Designed for the opposite conditions, they're no less than a safety hazard on cold, snowy or icy surfaces.

Winter Transmission Modes
Some vehicles with automatic transmissions have a special Winter mode that helps prevent slippage when accelerating (with or without traction control as a backup). They typically make the car accelerate starting in 2nd gear rather than 1st, then upshift as promptly as possible through higher gears. It may sound odd, but higher gears diminish thrust at the drive wheels, unless the engine is revving fast. Less force equals less slippage. Some automatics with manual-shifting modes let you start off in 2nd or 3rd gear to achieve the same effect.

Heated Seats, Steering Wheel
With leather upholstery in particular, heated seats are a must. One benefit is that they warm before the car's heat begins to flow. Offered mainly in front seats, the best give you several heat settings, but the most common is a high-low switch. In some cars, they're only fully on or off, but that's better than nothing. Relatively new are heated steering wheels, which solve the Hobson's choice of discomfort versus hazard - a freezing steering wheel or trying to steer with gloved hands.

Heated Side Mirrors
More common than ever, heated side mirrors can clear themselves of fog, melt accumulated ice or prevent further snow buildup. Many cars activate them along with the rear defogger, while some have their own dedicated button and a few are connected to the heated-seat switch.

Headlight Washer/Wipers
The little wipers you may have seen on luxury car headlights might seem extravagant, but they serve to clear grime, road salt and snow accumulation that can dim your headlights. Most cars that offer headlight clearing use washer jets alone, which have proven effective. Because the jets typically emerge from the bumper, spray then retreat, the feature is more stealth - and more common - than you might know. Some cars spray the headlights at the same time are the windshield is the headlights are on. Others have buttons that let you wash the headlights whenever you wish.

Heated Windshield
Though this feature is rare, some windshields are coated or impregnated with a thin film or fine wire grid that heats the glass itself, melting ice or loosening it in sheets. A shortcoming of the wire type is the exaggerated headlight glare that may take on a starburst shape.

Heated Wipers and Washers
A wiper de-icer, also known as a heated wiper park, frees wipers that are frozen to the glass where they rest, or "park." It also aims to keep the blades pliable enough that they contact the windshield over their full arc. Applied to windshield and/or rear-window wipers, the technology may be an option with its own button or a standard feature that works automatically in cold weather or along with defrosters. Heated nozzles and/or hoses and reservoirs serve to keep windshield washer fluid flowing in cold temperatures. It may help melt or clear ice, but mainly the feature should prevent the fluid from freezing once it lands on a cold windshield.

Remote Start
Most of the more esoteric winter-oriented features came along to alleviate the problems of a cold car. Here is where a remote start is a godsend. A warm cabin and clear windows make seat, steering wheel and supplemental window heaters a luxury instead of a necessity. A warm engine compartment can prevent wiper fluid freezing. The best remote-start systems automatically turn on the heat, defrosters and seats. Remote start isn't the most environmentally friendly feature, but it beats scraping ice in the frigid wind.

Retractable Hardtop (Convertibles)
People who have foregone convertibles due to their wintertime shortcomings have more choices than ever, thanks to the explosion of retractable - hardtop models. They're just like non-convertible cars when their tops are up. Why haven't you seen many? You probably have; you just didn't know it.

Block Heater
Compared to 20 years ago, cars today start almost flawlessly in cold weather. That said, there's cold ... and then there's cold. In the Northern states, where the temps often drop below zero and stay there, even the best-engineered cars need a hand. Block heaters that plug into a household electric outlet (typically overnight) keep the engine block warm (which keeps the oil thin), making starting easier and reducing wear and pollution. Electric dipsticks, battery warmers and other solutions are available as aftermarket products, but when a factory option is offered it's usually a heater that screws into the engine block or bisects a heater hose, where it warms and circulates the engine coolant.

Cars.com 2/16/09