You’re driving down a road when suddenly, your steering wheel begins to shake, and your car shudders as you pull off the side of the road. As soon as you exit your vehicle, you see the problem: you have flat tires. Hopefully, you have a good spare tire, or this event might take all day.

What is a spare tire?

Every car, truck, and SUV should have a spare tire mounted in the trunk or underneath the vehicle’s back end. If you’re having trouble finding your car’s spare tire, check your car’s owner’s manual. While reading that, look for the spare tire and your other tire’s proper inflation specs. This would also be an excellent time to check the maintenance section for suggested scheduled maintenance procedures. 

Car Doctor John Paul from AAA recommends checking your tire pressure often. You cannot rely on your car’s low tire pressure warning system, as it doesn’t apply to your spare, and it may not be accurate.

Instead, look at the inside door jamb on the driver’s side for a placard showing tire sizes and pressures. If your car has a compact or space-saver spare, sometimes called a donut, inflation specs are probably found in your owner’s manual or branded on the tire’s sidewall and will likely require higher pressures than your car’s other tires. 

How to properly inflate a spare tire

Armed with proper tire inflation specs, you’ll need a tire gauge to check the air pressure in your tires. If the pressure is low, you’ll need to inflate them to the proper specifications. Most convenience store gas stations have tire inflators. Some are free, and some charge a nominal fee. Tire dealers also offer inflation services but may have a waiting line if they are busy. The most convenient option is owning a tire inflator, a battery-powered plug-in to your car, or a larger air tank with a built-in compressor. 

When do you need a new spare tire?

All tires have a life expectancy based on the tire’s age. The tire’s manufacture date is a four-digit numerical code shown as two digits representing the week of the year and a two-digit year stamped in the tire’s sidewall; for example, a tire manufactured on March 25, 2022, would have a 1222 date code representing the 12th week of 2022.

Consumer Reports‘ Tire Program Manager, Ryan Pszczolkowski, suggests replacing your spare tire every 10 years. He also recommends frequent inspection for cracks and dry rot and properly inflating your tires regularly. 

Can I drive on a spare tire until payday?

People often wonder how long they can drive on their spare tire. There is almost no danger in driving on it for extended periods if it’s a full-size spare. The only downside is that if you have another flat, you’ll need another spare. However, driving on a donut presents a dangerous situation for your transmission. So, unless you’re only driving a short distance and not exceeding 50 mph until payday, it’s better to get it changed or find another ride. 

Where to turn when it’s time for a new spare

Full-size spares are available at any tire center and some online retailers. Keep in mind if you purchase a tire online, you’ll have to take it to a tire shop for mounting and balancing. Additionally, most auto parts stores, local tire centers, and online tire retailers carry or can order compact spare tires.

What you need to know about changing a flat

Finally, AAA offers car owners and drivers the following advice: When purchasing a car, don’t assume it has a spare. If not equipped with a spare, ask the seller to add one as an option. Also, make sure the car comes with the tools needed to change a flat tire and learn to use them.

Some vehicles are not equipped to carry a spare tire and have a tire repair kit instead. The repair kit provides users the means to repair simple flats caused by a nail or similar object through the tread but does little for significant damage or sidewall punctures. Owners of cars equipped with such kits should study their use and ensure the kits are up to date.