A mini spare tire (also known as a mini-spare, compact spare, space-saver spare, or, occasionally “donut”) is a temporary, limited-use spare tire designed for emergency use when a regular tire goes flat.
Mini spare tires typically are:
What is a Mini Spare?
Smaller in size than regular tires
A mini spare tire has a narrower width and smaller diameter than a full-size tire, conserving trunk space and reducing vehicle weight. The “donut” often employs a higher inflation pressure to support the vehicle’s size and weight despite its compact design.
Meant for limited use
Mini spares are Intended for short-term, low-speed use, generally no more than 50 mph, and less than 100 miles of travel.
Built to cost
Mini spares are generally of bias-ply construction and are manufactured with only a basic tread. As temporary replacements for “real” tires, mini spares generally provide less traction, compromised stability and handling, and are less-than-ideal in rain and snow.
So, why do carmakers equip cars with mini spares?
- Car designers place a high value on efficiency, cargo space, and weight reduction. A full-size spare tire takes up space in cargo area, and add 20-30 pounds to a vehicle’s weight. Plus, full-size tires cost more than do mini spares.
- Note that some cars are equipped with “run-flat” tires which are designed to safely travel longer distances, even when flat. Run-flat tires are most commonly found on sports cars and can be very expensive.
Pros and Cons of Mini-Spare Tires
Pros:
- Lightweight, compact, cheaper to manufacture
- Will get you safely to a repair shop, though no further
Cons:
- Vehicle performance limited by mini spare’s modest specs
- Should not be used for an extended period of time
- Driving with wheels of different size on the same axle can damage a vehicle over time
CG Says:
In short, a mini-spare tire is a practical but limited emergency solution for flats. Always check your vehicle’s manual for specific limits on your mini spare.
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What is a Mini Spare? Pictures
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