Sometimes, a temporary fix to your car can turn into a permanent one. For example, using a stop-leak product to seal up a small breach in your oil or coolant system. In such a case, there’s no need for further action as long as the leak doesn’t return.
On the other hand, there are circumstances where real action has to be taken asap, and temporary fixes just won’t cut it. A prime example of this is when you’re rolling on a spare tire.
So, how long can you drive on a spare tire? What factors influence its lifespan? What can happen if you don’t replace it? We cover all of these questions in this article – so read on!
Contents (Jump to Topic)
Key Takeaways
Type Matters – The type of spare tire you use (full-size, donut, or run-flat) is the main determinant of how long you can drive on it.
Other Factors – Tire pressure, speed limits, driving conditions, and the overall condition of your spare influence how long you can drive on it.
Know the Risks – Driving on spares can cause damage to your differential and makes accidents more likely.
Bottom Line – The simple answer to the above question is this: as short a distance as you can manage.
How Long Is It Safe to Drive on a Temporary Spare Tire?
By definition these tires are built to be temporary—that’s why they’re called “spares”. You’re supposed to use them in the event of an emergency.
The owner’s manual for your vehicle will tell you how long you should be driving on yours.
However, the amount of mileage you can use one for and stay safe while on the road can vary, as we’ll explain shortly.
For now, though, know that the general rule is to replace it as soon as you can.
What Factors Can Prolong or Shorten How Long You Can Keep Driving on a Spare Tire?
The factors that can shorten or extend a spare tire’s lifespan are:
- The type of spare.
- Overall condition.
- Is it properly inflated?
- Rough terrain.
- Speed and driving conditions.
Type of Spare
There are three varieties: full-sized, donut (space-saver), and run-flat. The type you have can make a big difference in how long you can keep driving on it:
Full-Sized
A full-size spare tire will be a match for the tires you already have. As long as it’s in good condition, it can serve as a replacement.
Most vehicles no longer have full-sized units included these days, though. Many manufacturers decided that the expense of providing an extra tire that will sit in the trunk indefinitely is too high.
Donut (Space-Saver Spare)
Donut tires are designed to be compact than other tires, being both lighter and smaller in size than full-size spare tires or regular tires. They can support your vehicle for a short time, but not indefinitely.
You shouldn’t go for more than 50 miles with a donut tire on your vehicle. It’s also crucial to avoid speeds over 50 miles per hour.
A donut spare isn’t built to withstand normal driving conditions for long, or carry you long distances!
Run-Flat Tire
Run-flat tires are more resilient against common road hazards. If punctured, rather than going flat or blowing out, they’ll still run.
(On that note, just in case you ever find yourself in such a situation, read this article to learn what to do when driving on a flat tire).
Now, you’ll still need to have the affected unit repaired or replaced as soon as you get a chance to do so. You just won’t have to go through the hassle of changing it—you can keep driving on it.
The manufacturer will tell you how long you can keep driving after you get a punctured tire.
Overall Condition
This applies mostly to full-sized and donut styles. What does the rubber look like? Does it appear visibly worn; are there cracks?
Tires don’t miraculously stop aging, even if they haven’t been used. Heat and oxygen will contribute to deterioration. Your trunk isn’t airtight, and it can get sweltering during the summer months.
Inflation/Tire Pressure – Is It Full?
Under-inflation is one of the factors that increase the risk of an accident with spare tires, or any tires for that matter. Any unit will perform poorly if it isn’t inflated properly.
Factors like slower stopping time, heat build-up, and poor handling can provoke a catastrophic blowout.
Rough Terrain
Driving on unstable terrain when the unit is already vulnerable will shorten spare tires’ lifespan. Think unpaved roads or streets that are pockmarked with potholes and cracks.
If your daily drive involves traveling over this sort of ground, expect to have to replace your spare sooner.
Speed and Driving Conditions
Slow and steady is the way to go with these temporary components. Try to avoid hard stops, abrupt turns, or speeding.
This means driving below 50 miles an hour—steel yourself for the slow lane!
What Could Happen If You Drive for Too Long on a Spare Tire?
Not only is it not safe to drive for a longer period of time than a spare can handle, but you can also end up causing severe damage to your car.
Consider these consequences:
- Increased accident risk.
- Damage to the differential.
Increased Accident Risk
Persistently driving on a spare tire can get you into an accident.
Remember, these units won’t last forever: it’s only a matter of time after a certain number of miles. Many models will offer less traction and result in poorer handling than a regular, full-size tire or full-size spares.
Damage to Differential
The differential in your vehicle compensates for each unit rotating at slightly different speeds. This is assuming both wheels are nearly identical.
Donut or space-saver models can wear the differential down over time. The smaller size will put extra strain on the component.
Conclusion
Now that all is said and done and you know how long you can drive on spare tires, you should be able to stay out of harm’s way.
In short, the answer to the question may disappoint you, since it’s along the lines of: as short a distance as you can manage.
The next time you think about using a spare tire beyond what it’s capable of handling, keep in mind that it’s preferable to pay for a replacement regular tire than get into an accident or damage your differential by driving around on a spare. Use the spare to get home or to a mechanic’s, and then put it to rest.
