12 Oct Changes in Tire Pressure with Cooler Temperatures
As winter and cold weather rolls in so does that pesky light on your car’s dashboard indicating low tire pressure. But really, how important is this light? And should it be ignored?
The answer is no! Low tire pressure impacts breaking, gas mileage, tire wear, the handling of your vehicle and can even cause a dangerous blow out. It is important to have the correct amount of air in your tires because air pressure helps support the vehicle’s weight and contributes to safe driving and overall performance.
Tire pressure can be monitored using a tire gauge or a tire pressure monitoring system (TPMS), which is in most new cars. Tire pressure is measured in pounds per square inch and is a unit of pressure also known as PSI. Normal PSI for a tire is around 32. As tempting as it is to ignore tire pressure, you should use a tire gauge to check the pressure when a light comes on your dashboard. If you check and the pressure is anywhere within 1 PSI of normal, it’s fine to leave the air in the tire as is.
For every 10 degrees that the temperature drops, the PSI of your tires goes down by 1. It is best to check the PSI when your tires are cold because it gives the most accurate reading. Even having your car parked in a garage can affect the PSI. This is because the tire pressures is adjusted to the inside temperature and not to the chilly outside air. It is always best to check the temperature and then adjust the PSI. Realistically, most people will not have time to do this whenever the weather affects a car’s tire pressure. So, as a general rule of thumb, over inflate your car’s tires before temperatures drop by 2 to 3 PSI. Your vehicle’s tires may wear a bit faster and have a rough ride until the temperature drops. However, inflating early is the best way to prepare for a drastic temperature drop in fall and winter.
Nitrogen vs Oxygen and How it Affects Tire Pressure
As the air gets colder, it contracts. This causes air molecules to come close together and the volume of air in tires to decrease. This is why a good alternative to oxygen in tires is nitrogen. A nitrogen molecule is larger than oxygen which reduces the amount of inflation a tire loses and helps pressure to stay higher. Nitrogen, unlike oxygen, doesn’t contain moisture. This has a large effect on inflation as water vapor is what contributes to a pressure drop in tires. No water vapor means drastically less change in a tire’s pressure. Using nitrogen reduces seepage out of the tire and helps avoid low tire pressure. Nitrogen can be put in your tires at multiple local locations.
Check your tire pressure
If you’ve never checked your tire pressure, it’s the perfect time to start. First, find out if there is a tire pressure monitoring system installed in the vehicle. If it doesn’t have one, get ready to do it the old fashioned way!
- Make sure your tires are cold or your car has not been driven in at least a few hours in order to receive an accurate reading
- Start by removing the cap on your tire valve
- Insert your tire gauge into the tire valve
- The measurement will shoot out on the other side of the gage giving you your PSI
- Repeat a couple of times on that tire to ensure the reading is accurate
- Repeat on the 3 other tires