Can a smaller spare tire be used?
3 Answers
A smaller spare tire can be used. It is almost an unwritten international convention to have a smaller spare tire. In Europe and America, some cars not only have smaller spare tires but some models even mark them with different colors. Smaller tires occupy less space, weigh less, and can save some gasoline in the long run when carried daily. Types of car spare tires: 1. Full-size spare tire: The specifications of a full-size spare tire are exactly the same as the other four tires on the car, and it can replace any temporarily or permanently unusable tire. 2. Non-full-size spare tire: The diameter and width of this type of spare tire are slightly smaller than the other four tires, so it can only be used as a temporary replacement and must be used on non-driving wheels, with a maximum speed not exceeding 80km/h. 3. Run-flat tire: Also known as a safety tire (run-flat tire), commonly referred to as a "bulletproof tire," the industry directly translates it as "tire that can run without air."
Last time my car tire got punctured, I put on that spare tire and noticed it was a size smaller, which really worried me at the time. I asked a mechanic friend about it, and he said these compact spare tires are temporary, designed just for emergencies and not meant for long-term use. The main issue is that the different wheel size affects the car's balance, making the steering feel off, and it might even rub against the body. You need to keep your speed in check—don’t go over 80 km/h—and ideally, get to a repair shop within a few dozen kilometers to replace it with a regular tire. Avoid sudden acceleration or braking, and take turns slowly. I personally tried driving a short distance home, about 5-6 kilometers, and it was fine, but it’s definitely not safe for highways. If this happens, don’t push it—calling a tow truck or driving carefully to a repair shop is the smarter move.
I've seen many cars equipped with a spare tire that's one size smaller than the regular tires. From a mechanical perspective, this compact spare tire is a temporary solution designed by manufacturers to save space. The difference in wheel diameter can cause track deviation, affecting the vehicle's handling stability, especially during turns or on slippery roads where skidding is more likely. The speed must be strictly limited to 70-80 km/h, and the distance should not exceed 50 km; otherwise, the suspension and drivetrain may be overloaded and damaged. My personal advice is to always check the spare tire's air pressure before use, avoid high-speed or long-distance driving after installation, and restore the original tire as soon as possible. Don't underestimate this issue—it directly relates to driving safety.
