5 tips to keep your car in peak condition during frigid winter weather

Your vehicle’s battery is especially hard hit when the mercury plummets. Cold temperatures reduce its cranking power. In fact, at about 0° F, a battery has only about half the cranking power it has at 80° F.

To check a conventional battery, remove the plastic caps on the top and check the fluid level. (See your owner’s manual.) If the fluid is low, add distilled water. On maintenance-free batteries, check that the window at the top of the battery indicates a fully charged state. If it’s more than five years old and shows signs of weakness, replace the battery with a top-rated model.

You  can have the battery professionally tested at a service station, auto parts store, or repair shop. A tired battery may just need to be charged. But if it’s defective or just worn out, it’s best to replace it before it goes completely dead. (Check our buying guide and Ratings for car batteries. Worst case, be sure you know how to jump-start a car.)

You have to replace wiper blades more often than you might think. Our tests have found that even the best-performing wiper blades start to lose their effectiveness in as little as six months. Streaks or missed expanses of glass are sure signs that the blades are ready for retirement.

While it’s possible to stretch their life by cleaning the rubber edge of the blade periodically with a paper towel and glass cleaner, it isn’t safe to do that all winter long. Instead, get yourself new blades. We recommend replacing wiper blades as often as twice per year. Most wiper blades are easy to install, and some stores, such as Advance Auto Parts, will perform the replacement work free of charge.

Get more information in our guide to winter driving.

If you can’t see out the windows, you’re a danger to yourself and everyone around. Don’t try to use the wipers and those brand-new wiper blades to remove ice from the windshield. Instead, use an ice scraper on frosty mornings. If you park outside, place the wipers in the raised position when it’s going to snow overnight to keep them from freezing to the windshield.

With dirt, mud, and salt residue being kicked up off the road, it’s likely that you’ll be using your windshield washers a lot, so keep your windshield-washer reservoir filled with a winter-blend washer solution that contains an antifreeze agent.

Also make sure the heater is functioning properly and that plenty of warm air is being directed to the windshield when it’s in the defrost mode. To help prevent your windshield from fogging up, run the air-conditioning system (with the temperature set at a comfortable level) to dehumidify the air.

Finally, check that all the vehicle’s lights are working properly, so that you’ll have optimum visibility at night and motorists front and rear will be able to see you.

Cold weather can beat up your engine, too. Motor oil thickens when cold, making it harder for the engine to turn over. Check your owner’s manual for the manufacturer’s recommendation. Generally, you should be using multi-viscosity oil that has a “W” in the viscosity index, signifying that it’s formulated for winter use. Typical formulas that are recommended for modern engines include 5W-20, 5W-30, and 10W-30, which provide good oil flow at low temperatures and can often be used year-round. Whenever you have the oil changed, replace the oil filter as well to ensure the system has the maximum amount of flow.

While the car is in the shop, have the radiator and heater hoses checked for cracks, leaks, or contamination from oil or grease. The hoses should be firm yet pliable when you squeeze them. Scrap them if they feel brittle or overly soft.

Try to keep your coolant mixture in a 50/50 ratio of antifreeze and water. This will keep your coolant from freezing until temperatures are well below zero. Colder conditions, however, can call for a 60/40 or 70/30 ratio. Under no circumstances should you use a higher antifreeze-to-water ratio than this.

Spinning out in the snow and ending up in a ditch isn’t the best way to discover your tires are worn out. So if you’ve been waiting to pick up a new set of tires, don’t delay as your safety depends on tire traction and winter-grade tires tend to be in short supply when the snow begins to fall.

If your area gets occasional snow, a new set of all-season tires should do the job. Look for a highly rated set that has performed well in our snow-traction and ice-braking tests. (Check our tire buying guide and Ratings.) Remember that it’s safest to replace all four tires at one time.

If you live where snow and ice are ever-present, consider buying dedicated winter tires mounted on inexpensive steel wheels. These have tread patterns and rubber compounds specially designed to grip snow and ice for optimum traction on slick roads. Winter tires typically have shorter tread life and generate more road noise than the all-season tires that your vehicle came with. But the extra safety they provide is generally worth the compromise.

Finally, keep a roadside emergency kit in the car.

—Jon Linkov