How to Prepare Your Car for Winter: The Maintenance Checklist That Prevents Failures
Cold weather creates specific challenges for every major vehicle system: batteries deliver less starting current, engine oil flows more sluggishly, tires lose pressure, washer fluid freezes in the reservoir and lines, and the cooling system’s freeze protection may be inadequate for the season’s lows. A pre-winter inspection and maintenance session in October or November addresses all of these vulnerabilities before the first severe weather event rather than discovering them in a parking lot at minus ten degrees.
Battery: The Most Common Cold-Weather Failure
Battery capacity decreases by approximately 20 percent at freezing temperatures and by 50 percent at minus 22 degrees Fahrenheit — the chemical reactions that produce electrical current slow significantly in cold conditions. A battery that starts a car normally in warm weather may fail to start it in cold weather if it’s approaching end of life. Test your battery’s cold cranking amp capacity with a load tester — available for free at AutoZone — before winter. A battery showing more than three years of service with a load test near its capacity limit warrants replacement before winter rather than during it.
Tire Pressure and Winter Tires
Tire pressure drops approximately one PSI for every ten degrees Fahrenheit of temperature decrease. A tire correctly inflated at 35 PSI on a 70-degree day may be at 29 PSI on a 10-degree morning — well below the vehicle’s specified operating pressure, which reduces handling and braking performance. Check and correct tire pressure at the start of winter and monitor monthly. In climates with significant snow and ice, dedicated winter tires provide dramatically better traction than all-season tires — the rubber compound in winter tires remains pliable in cold temperatures where all-season compounds stiffen and lose grip.
