A spare tire is a temporary fix, not a replacement
You can drive on a spare tire, but not for long. Most spares are designed to get you to a tire shop safely—typically 50 to 70 miles at speeds under 50 mph. Driving beyond that distance, at highway speeds, or in bad weather puts real stress on a tire that was never meant for regular use and risks damage to your vehicle's drivetrain.
The exact distance depends on which type of spare you have. A full-size spare (rare on newer cars) can handle longer distances. A temporary donut spare (the small, skinny tire most vehicles carry) has the shortest safe range. Run-flat tires, which some luxury and performance vehicles use, can go further but still have limits. Ignoring these limits doesn't just risk a blowout—it can damage your transmission, differential, and suspension.
Key Takeaways
- Temporary donut spares should not be driven more than 50 to 70 miles or faster than 50 mph, even if the tire feels fine.
- Full-size spares can handle longer distances and highway speeds, but you should still replace them with a permanent tire as soon as practical.
- Driving on a spare for extended periods stresses your transmission and differential because the spare is a different size than your regular tires.
- If you cannot reach a tire shop within the safe distance, call a mobile tire service or tow truck rather than pushing the spare beyond its limits.
- Check your spare's air pressure when you first get a flat—many spares sit unused and lose pressure over months or years.
Why spare tires have distance and speed limits
A temporary donut spare is smaller and thinner than a regular tire. It is made from cheaper rubber and carries less weight. These differences mean it wears out faster and cannot handle the same forces a full tire can. The sidewalls are thinner, so they flex more under load, which generates heat. Push a donut spare too hard or too far and the rubber breaks down, the tire can fail suddenly, and you lose control.
The bigger problem is what happens to your drivetrain. Your vehicle's transmission and differential are calibrated for tires of a specific size. When one tire is noticeably smaller—as a donut spare is—it rotates faster than the others. Your transmission has to work harder to compensate. The differential, which distributes power to the wheels, is also thrown off balance. Drive this way for hundreds of miles and you can damage both systems, leading to repairs that cost far more than a new tire.
This is why your owner's manual lists a specific distance limit. That number is not conservative—it is the point at which damage becomes likely, not just possible.
Donut spares versus full-size spares
Most cars built in the last 15 years come with a temporary donut spare. It is light, takes up little space, and costs the manufacturer less. The trade-off is that you can drive on it for only 50 to 70 miles at 50 mph or less. Some manufacturers say 50 miles; others say up to 70. Check your owner's manual for your vehicle's exact limit.
Older vehicles and some trucks still carry a full-size spare—a regular tire that matches or closely matches your other tires. A full-size spare can handle highway speeds and longer distances because it is built to the same standard as your regular tires. You can drive on it for several hundred miles if needed, though you should still replace it with a new permanent tire as soon as you can. A full-size spare that has been sitting in your trunk for years may have lost air pressure, so check it before you rely on it.
If your vehicle has a full-size spare, treat it as a real tire and rotate it into your regular rotation every few years. If it sits unused, the rubber hardens and the sidewalls weaken, making it unsafe even though it looks fine.
Run-flat tires and what they allow
Some vehicles, particularly BMWs, Mercedes, and performance cars, come with run-flat tires instead of a spare. A run-flat tire has reinforced sidewalls that can support the vehicle's weight even after a puncture. You can drive on a run-flat for 50 to 100 miles at reduced speed (usually 50 mph) after a flat, depending on the tire and manufacturer.
Run-flats are convenient because you do not have to change a tire on the roadside. The downside is that they are stiffer, which makes the ride harsher, and they cost more to replace. If your vehicle has run-flats, your owner's manual will tell you the exact distance and speed you can drive after a puncture. Do not exceed those limits—the tire will fail, and you will have a much bigger problem than a flat.
What to do if you cannot reach a tire shop in time
If you are more than 70 miles from a tire shop, or if you are on a highway where stopping is unsafe, do not try to stretch your spare's range. Call a mobile tire service or a tow truck. Mobile services can come to you and install a new tire on the spot, often within an hour. A tow truck will take your vehicle to a shop. Both options cost money, but they cost far less than repairing transmission or differential damage.
If you are in a rural area with no cell service, drive slowly and carefully to the nearest town. Keep your speed under 50 mph, avoid sudden turns and hard braking, and pull over if the spare feels unstable or if you hear unusual noises. A slow, cautious drive at low speed is safer than a fast one, even if it takes longer.
Before you drive anywhere on a spare, check its air pressure. Use a tire gauge to see what pressure it has. Many spares lose air over time and may be underinflated. The correct pressure is printed on a label inside your driver's door jamb or in your owner's manual. Inflate the spare to that pressure before you drive.
Signs your spare is failing and you need to stop
While driving on a spare, watch for these warning signs. If the spare feels soft or squishy when you press on it, it may be losing air—pull over and check the pressure. If you hear a thumping or rhythmic noise from that wheel, the tire may be separating internally. If the vehicle pulls to one side or feels unstable, especially at speed, stop when ready and do not continue.
If the spare is visibly damaged—cracked, bulging, or leaking—do not drive on it at all. Call a tow truck. A damaged spare can fail suddenly and leave you stranded or cause an accident.
Even if the spare feels fine, stick to your vehicle's distance and speed limits. The tire may feel okay at 60 mph for 100 miles, but the damage is happening inside where you cannot see it. By the time you feel a problem, it may be too late to stop safely.
Replacing your spare after you use it
Once you have driven on your spare, replace it with a new permanent tire as soon as you can. Do not put the spare back in your trunk and forget about it. A donut spare that has been driven on is worn and should not be used again except in a true emergency. A full-size spare that has been driven on should be inspected by a technician to see if it is safe to keep as a spare or if it needs to be replaced.
While you are at the tire shop, ask them to inspect your other tires for damage. A flat often happens because of a puncture, but sometimes it is a sign that your tires are worn or your alignment is off. If you have had multiple flats, your alignment or suspension may need attention.
Frequently Asked Questions
Can I drive on a donut spare to work every day?
No. A donut spare is for emergency use only. Driving it daily, even short distances, will wear it out quickly and damage your transmission and differential. Replace your flat tire with a new one as soon as possible.
What if my spare is flat when I need it?
Check your spare's pressure every six months. If it is flat, inflate it before you need it. If you discover it is flat when you have a flat tire, call a tow truck. Do not drive on a flat spare.
Is it safe to drive on a spare in the rain or snow?
No. A spare tire has less tread and less grip than a regular tire. Rain and snow make this worse. If you must drive on a spare in bad weather, go very slowly and avoid highways. Consider calling a tow truck instead.
How do I know if my vehicle has a full-size or donut spare?
Open your trunk and look. A donut spare is small and thin. A full-size spare looks like a regular tire. Check your owner's manual for the exact type and the distance limit for your vehicle.
Can I patch or plug a spare tire and keep using it?
A temporary donut spare should not be repaired. If it is punctured, replace it. A full-size spare can sometimes be patched if the damage is small and in the tread area, but have a technician inspect it first. A spare that has been driven on and then repaired may not be safe.