We live in a culture of winter survival techniques. This tactic can be seen everywhere: four-wheel drive cars, four-wheel-drive vehicles, and the classic litter box hidden in the trunk like some kind of automotive emergency kit. The goal is always the same. Get an edge. Keep the car moving. Avoid slipping.
Most of these strategies are reliable. Accident prevention is clearly better than surviving an accident. But there is a trick in the collective mind of drivers who think they know better. Under-inflated tires can be useful when driving on snowy roads.
This is not true. You might end up in trouble or worse, stuck.
To understand why this myth died so quickly, we need to look at the physics. Especially the bet. Traction is simply friction between two surfaces. In the case of a car, the rubber comes into contact with the road surface. The greater the friction, the greater the grip. Increased grip means you won’t slip on ice.
An important measure here is the contact patch.
The illusion of a contact patch
The contact patch is a small rectangle of rubber that actually touches the road. Physics tells us that the larger the contact area, the more grip it usually has. This is why people think it’s a good idea to let the air out of your tires.
When the air pressure drops, the tire deflates. It sinks. The sidewalls are curved. Suddenly there was more rubber on the ground.
It works well in sand. Suitable for floating on deep and loose snow. In these special conditions, a lower pressure is preferred.
What about the streets in winter? There aren’t that many of them.
Friction on snow plowed roads
This is a problem that occurs when your winter tires are under-inflated on a clear road. You’re getting “too much” traction in the wrong place.
Without enough air pressure, your tires will become wider and flatter. On the streets where the snow had been plowed, large areas of rubber stuck violently to the asphalt. It doesn’t roll smoothly. It drags. The steering wheel shakes. The wheels are fighting you. Accuracy is lost. A car that doesn’t drive well is a liability.
Another thing is the depth of the snow. Properly inflated tires have a stiffer profile. They made it through the shallow mud to the footpath below. Insufficient tire pressure? It runs on snow like a canoe. Instead of digging into the road, the necessary friction allows it to float.
Also, you destroy your gear. If the expansion is not sufficient, excess heat is generated. The shoulder of the tire wears unevenly. It can damage the rim. This is a lose-lose situation and nothing short of a little air pressure can save it.
So skip the idea. Keep the tires at the PSI recommended by the manufacturer.
Checking the actual status of cat litter
While you shouldn’t mess with tire pressure, it’s actually a good idea to keep kitty litter in your trunk.
If you get caught drifting, throw some litter under the drive wheels and you’ll get traction. This increases the friction needed to get the tire out of the hole. It is very cheap. This works well.
So when will spring come? Every stray cat in the neighborhood has its own toilet. It’s a win-win.
Frequently asked questions about winter tire pressures
What should my tire pressure be in winter?
Aim for 30-35 PSI. Most manufacturers specify this range. Lowering it lowers fuel economy and makes it difficult to control the car.
Should I inflate my tires in cold weather?
Yes. Cold air contracts. As the temperature drops, tire pressures drop. Check back often. Low air pressure on snow or ice is dangerous because it reduces your ability to stop and turn.
At what temperature should I check tire pressure?
Tire manufacturers recommend checking air pressure when daytime temperatures are around 70°F and nighttime temperatures are around 20°F. At the moment, the air inside the tire is in the most stable state for the measurement.
**How to adjust tire pressure in winter? **
First, find a recommended PSI. It can be found in the owner’s manual or on a sticker inside the driver’s door frame. Remove the valve stem cover. Install the pressure gauge. Add air if necessary and close the lid. Simple.
What is the best PSI for my tires?
Standard pressure is 30-35 PSI. It depends on the load on the car and the type of tires. But in general, staying in this range keeps the contact patch in optimal condition. Not too big. Not too small. Perfect for the road underfoot.
