Until a tire runs flat, most people don’t give their tires a second glance. This is a dangerous practice since properly inflated tires are vital for safety by improving both handling and traction.
During the cold winter months, driving with properly inflated tires becomes even more important since traction is reduced and driving under poor weather conditions means that you will need all the added traction you can get!
Is it OK to inflate my tires when cold weather strikes, though? Do I need to do anything differently?
Today, we are going to answer the most common questions about inflating the tires on your car during cold weather.
First- A Little Science
Cold weather does affect your overall tire pressure. When temps drop, the air molecules move slower and they huddle together (how cute). When temperatures increase, these molecules begin moving faster and farther away from each other.
For every 10 -degree change in temperatures, your tires can gain or lose as much as 2 pounds PSI. This means that when the temperature drops 20-degrees at night, your tires can be 4 pounds less than they will be later the next day when the temperatures heat up.
So How Can I Inflate My Tires When It Is Cold?
This is going to depend on the range of temperatures you are experiencing and how long you expect it to last.
A small decrease, such as 2-4 pounds, is nearly impossible to see on the average tire. It can, however, have an impact on the way the tire handles the road.
This is why it’s a good idea to check your tire pressure every other fill-up or a minimum of once a month.
If your TPS light only comes on first thing in the morning, this could be due to a drop in the temperatures at night.
For areas that have months of very cold, snowy weather, you should check your tires in the morning before you drive the car. The manufacturer tire pressure readings should be on a plate or label on the inside of the driver’s door. This number is assuming that your tires are cold.
For example, if your tires should be set at 32PSI and when you use your gauge to measure the air, it reads 28, you need to add 4 pounds of air to the tire. This is easier to do if you have a compressor or tire inflator. You could drive down to the local gas station and only put in 4 pounds, regardless of what the gauge reads then.
Won’t the Tires be Over-Inflated Later On?
This is the reason you see many people recommending checking tire inflation every week. Yes, you want to get good traction, but you don’t want to be out in the snow or even in your garage every day, checking the tire pressure. That might earn you endearing labels such as OCD.
Yes, your tires might have a few extra pounds during the day as you drive. An alternative is to set the tire pressure about 1 or 2 pounds lower when the tire is cold and as you drive the tire pressure should be about perfect.
The problem with underinflated tires is that they tend to have more blow-outs. You might hear old-timers say that you get better traction when tires are very underinflated (such as 10 pounds) and while this might be true, that improved traction might lead to an accident when the tire blows out.
What If I Park My Car in a Heated Garage?
For those of you who live in the very cold North or Eastern part of the country and you have a heated garage, remember that the temperature of the garage will also affect the air pressure in your tires. This means that checking your tire pressure in the garage and then driving outside to the cold weather means you will probably lose at least 1 pound of air by the time you hit the end of your driveway.
Add about 1 pound over the recommended PSI if you have a heated garage.
The Bottom Line
Tire pressure in the cold winter months can be a bit of a hassle. Chances are that you’ve seen people driving with obviously under-inflated tires.
Since under-inflated tires are far more likely to blow out than slightly over-inflated tires, the latter is preferable. As things warm up in the Spring, you will need to adjust your tire pressure once again.
Check the tire pressure on your vehicle when it has been sitting (preferably all day or all night). Add the amount of air that is necessary to bring your car up to the recommended tire pressure as stated by the manufacturer. As you drive, the air inside the tires will warm up and might cause the tires to be a bit overinflated. If you are curious just how much, you can measure the air pressure when you reach your destination.
Most experts do not recommend that you release air when the tires are warm to prevent them from being under-inflated.
Over time, you will get the hang of what PSI works best for your car depending on the air temperature. When summer finally arrives, at least you can set your tires and forget about them for a few months!