A spare tire can be a lifesaver when it comes to keeping you safe on the road. When something goes wrong with one of your other tires, a spare tire can get you to a safe location where you can get a replacement. But for your spare tire to do the necessary work, it’s got to have the right PSI. But what PSI should a spare tire be?
PSI (pound per square inch) is key to making sure that your tires function as they should. You’ll learn about PSI and spare tires here.
Key Takeaways
- A “donut” spare tire should have a PSI of 60.
- A full-sized tire should have a PSI of between 30 and 60.
- Find out the PSI required for your specific tire for best performance and safety on the road.
What PSI Should I Have in My Spare Tire?
Your spare tire’s PSI should be 30 to 60 PSI or 4 BAR. This will allow the smaller tire to have enough pressure to keep up with the weight of your vehicle. It is only meant for temporary use before you go to a mechanic to repair or replace your tire. Make sure to drive carefully and slowly on a spare tire to stay safe until you get the tire replaced.
The exact PSI you want for your tire depends on the type of spare tire you have. If you utilize a smaller, save space “donut” tire, you need to have the PSI a little bit higher.
These tires are smaller in order to save room inside your vehicle. Make sure it has a relatively high PSI so that it can deal with the weight of your vehicle until you can get it replaced.
You need to get the PSI up to 60 in a temporary donut tire to keep you safe on the road.
On the other hand, if you have a full-sized tire, such as those found on SUVs, trucks, and other heavier vehicles with a heavier load, your tire will need a different amount of PSI.
Most of these full-sized spare tires will need to be somewhere between 30 to 60 PSI before you can use the tire safely.
How do you know what PSI to use for a full-size tire? It should be somewhere between 30 to 60 PSI, but that is quite a range.
Take a look at some of the markings on the tire to find out the correct pressure.
How to Check the PSI of a Spare Tire?
It is important to check the pressure of your spare tire on occasion to make sure that it is still at the right levels.
The most convenient way for you to do this is by using a tire pressure monitor. However, if you already have an air pump, attaching it to the tire valve can give you a good reading, too.
What Happens When the PSI on a Spare Tire is Too Low?
A spare tire that you store in your vehicle will end up losing some of its PSI over time. If you end up putting it on your car without checking the PSI, this could be a dangerous situation.
If you use a spare tire that doesn’t have the right PSI, you may end up with the following problems.
The Tire May Go Flat
Even the spare can go flat if the PSI is too low and you try to drive on it too long.
Tire Failure
If the PSI is too low, the spare tire will fail and may blow out. This can leave you stranded on the side of the road.
Compromised Handling
Driving on a tire that has a too low PSI is going to make it very difficult to drive the vehicle safely.
If the weather is bad or there is ice and water on the road, you could end up in an accident.
Uneven Wear
Uneven wear on a tire can make it stop working earlier and will ruin the tire so you can’t use it.
Should I Air My Spare Tire to the Max PSI?
It is not a good idea to go to the upper limit for PSI on your tires.
Maybe you think this is an efficient way not to have to worry about the tire running out of air too quickly. But this becomes a problem when you encounter conditions like cold or hot weather, and even by maneuvers like cornering.
To make sure that you are safe, no matter the driving conditions, it is best to pressure the tires just a bit below the specified amount for PSI.
No matter how much the tire can potentially take, it is best to never exceed the limits that are listed by the manufacturer.
If you add too much pressure to the tire, it can lead to loss of control when driving the vehicle and even serious injury.
What Happens if You Use the Spare Tire Too Long?
Your spare tire is not designed to do long-distance driving or for you to travel at high speeds.
They are a temporary solution that allow you to get to a mechanic to repair or replace your tire. It is best to not go further than 50 miles, or faster than 50 miles per hour, on the spare tire.
If you drive around on the spare tire too long, you risk damage to the tire as well as to other components of the vehicle.
How Long Will My Spare Tire Last Unused?
The spare tire can last a long time if you do not place it on the vehicle. If you haven’t used the tire, it may last up to eight years.
The type of storage that you choose for the spare tire will help affect its lifespan. For example, a tire stored in your trunk will often last longer than one placed under the vehicle.
You should check the PSI in your spare tire at least twice a year. You can use an air gauge to help you tell how full the spare tire is.
The gauge will tell you whether the spare tire is at the right PSI. If you find it’s necessary, you can add air at the gas station or with your own air pump.
Final Thoughts: What PSI Should a Spare Tire Be?
Having a spare tire is a lifesaver if you’re on the road and something goes wrong with one of your regular tires.
Taking care to keep the spare tire at the proper PSI will ensure that the tire will work well when you need it the most.