Precipitation combined with freezing temperatures makes winter driving hazardous, regardless of the vehicle you drive. To improve safety, it’s important to winterize your vehicle and outfit it with the right winter tires.
In the warmest parts of the country, all-season tires rated for snow performance are suitable for the winter months, but if you regularly drive on snowy, icy roads, you’ll need true winter tires.
Manufacturers are blurring the lines between all-season and winter-specific tires, and knowing the difference is crucial. Here’s how to choose the correct winter tires for your vehicle.
Understand the Ratings
3PMSF: Tire makers apply the Alpine symbol – also known as the three-peak-mountain with snowflake (3PMSF) – to any tire that passes minimum performance requirements on snow. This is known as the snow grip index, or SG. In the past, only dedicated winter tires bore this symbol, but some all-season tires carry the marking
today, which can make shopping for winter tires confusing.
M+S: The M+S symbol displayed on an all-season tire indicates it will perform well in moderate winter conditions. M+S means mud and snow.
All-season tires marked with M+S, or the three-peak mountain snowflake symbol and M+S, are designed with enough grip to handle modest amounts of snow and ice. All season-tires with these markings will perform better than those without markings, but no all-season tire performs as well as a true winter tire.
The Anatomy of a Winter Tire
Performance winter tires are built differently than all-season tires. They’re made from a flexible, hydrophilic rubber compound that provides more traction on snow and ice.
The tread design is also different from the lateral grooves identifiable on most all-season tires. Winter tires boast sharp, irregular tread blocks and larger grooves between lugs to help the tire cut through and displace snow, creating closer contact with the road.
True winter tires are siped, meaning they have numerous slits in the lugs that provide added grip. These anatomical differences make winter tires more aggressive than all-season models branded for mud and snow.
In general, there are three different categories of true winter tires: performance, studded and studdable.
Studs are lightweight metal pins embedded into the tread of winter tires. Like snow chains, they dig into compact
snow and ice, improving traction. They have drawbacks: They’re noisy and have the potential to damage pavement.
For this reason, states have varying regulations on what time of year studs are allowed on public roadways, if at all. The U.S. Tire Manufacturers Association published a list of studded tire regulations as of November 2018 for passenger cars, but recommends double-checking with your state or local Department of Transportation.
While studded tires perform best in extreme conditions, extra tread depth is needed to accommodate studs, which limits studded tire size options.
Studless tires have more advanced winter tread compounds, which means they’ll outperform studded models in all but the slickest conditions. Studless tires handle best in slush and packed snow.
If you’re unsure whether you’ll need studs, consider investing in studdable tires, which feature performance tread but can accommodate the addition of studs if desired.
Extra Tips for Purchasing Winter Tires
When purchasing winter tires, keep these five tips in mind to ensure your vehicle handles safely in winter conditions:
- Pay attention to sizing when buying a new set of tires. Generally, it’s best to use the same tire size as the OEM.
- Cold temperatures drop your tire pressure. On average, a tire loses 1 PSI for every 10-degree Fahrenheit temperature drop. Check your tire pressure regularly to maintain optimum performance. The recommended tire pressure is the same for winter tires as for other tires.
- Always buy four matching tires. It’s tempting to save cash and only buy two, but this creates uneven traction, which could be hazardous. Uneven tire tread can also damage the transmissions on some vehicles, so buying four tires up front is the most economical, long-term choice.
- Check your tires for wear at least once a month. After roughly five years of use, you should have them inspected annually. Replace tires when the wear bar indicator is visible.
- Properly storing your winter tires extends their lifespan. Clean each tire thoroughly before putting them in storage and keep the tires cool, dry and out of direct sunlight.