In winter, tire pressure levels can change dramatically, having a significant impact on your ability to control your car on snow and icy roads.
Maintaining the correct air pressure in cold weather can be tricky. As the temperature drops, so does the air temperature inside your tires, causing the air to contract and lowering the air pressure in the tires. Generally, for every 10 degrees Fahrenheit drop in temperature, your tires can lose about 1psi of air pressure. Sudden drop in temperature can reduce your tire pressure significantly, so the key to maintaining correct tire pressure in the winter is to pay attention to temperature swings and adjust your tire inflation accordingly.
Winter tire pressure can also be affected by variances during the day. If you set your tire pressure in the afternoon, overnight as temperature drops your tires will cool and tire inflation will go down.
That is why some vehicle manufacturers recommend setting winter tire pressure 3 to 5 psi higher than their recommended inflation levels. This actually makes sense, and here is why.
Winter tires feature more aggressive tread designs, softer tread compounds and deeper tread depths than summer or all-season tires to provide more traction in snow and on ice, but these characteristics also reduce steering responsiveness. Adding 3 to 5 psi above the recommended inflation pressures helps increase tire stability and improve responsiveness.
Air temperatures in winter are significantly lower than typical summer temperatures, resulting in tires to run cooler and build up less heat inside the tire. Inflating tires 3 to 5 psi higher than their recommended offsets the reduced hot tire pressures resulting from less heat buildup.
Just remember to check your tire pressure more often during colder months to keep your ride safe and comfortable on winter roads!