Why is the spare tire always smaller than the main tire?

Spare tires have always been an indispensable part of cars, ensuring that the car can continue its journey without interruption when the main tire has a problem. Technology development has made the world produce many different types of tires.

According to Edmunds, spare tires used to be the same as the main tires, but from 2007 to 2014, the number of full-size spare tires worldwide decreased by about 49%. According to statistics from this site in 2014, about 52% of cars worldwide used small spare tires, mostly passenger cars. So why are there these differences, let's continue to follow.

The reasons why spare tire manufacturers produce smaller spare tires than the main tires are compiled by Yourmechanic from technical experts, including: Small spare tires help reduce the space occupied in the trunk, Light weight reduces the vehicle load, saving fuel; Light weight also makes it easier for drivers to carry, move and replace; Smaller tires are often lighter and have lower traction, and can run at a lower maximum speed, usually around 80 km/h. This reminds drivers not to forget to go to the tire repair shop, replace the main tire and adjust it.

If the spare tire is the same as the main tire, it often makes the user "lazy" and does not go to the workshop to check, causing unsafety. Finally, producing smaller, lighter spare tires also helps car manufacturers save costs and reduce car prices.

There are still manufacturers of spare tires that are the same size as the main tires. This type of tire has two types, one is the same size and technical quality, the other is the same size but the technical quality is not the same, for example, the tread is shallower, the rim is not as stiff...

The type that is identical to the main tire is often used for vehicles that have to carry heavy loads and run long distances such as trucks, pickup trucks, and large SUVs, while the type with lower technical quality is often used for larger vehicles that mainly run in urban areas and do not carry heavy loads, such as crossovers and MPVs.

Why do some cars not need spare tires?

Because the car uses run-flat tires, which can still run hundreds of kilometers at high speed after being punctured. However, to ensure maximum safety, these cars are still equipped with spare tires.

Principles to remember when changing spare tires:

Changing the spare tire is one of the top priorities every driver should know. Here are some rules:

1. For safety of people and property, when changing tires, chock the wheels, lock the doors and turn on the warning lights.

2. Place the jack in the correct position. This position is usually marked on the car frame about 15-20 cm from the tire. Placing it in the wrong position can cause the jack to become unstable, affecting the structure of the car.

3. Remove the screws in a star pattern. That is, do not remove the screws next to each other continuously, but remove the screws diagonally (for example, number 1 then number 3, then 5-2-4).

4. Screws - jack - screws. That is, when removing, loosen the screws, raise the jack, then remove all the screws. When screwing in, do the same, tighten the screws, lower the jack, then tighten. 5. Place the spare tire under the car. Place the spare tire under the car in case the jack falls, there is still a tire to support it so it doesn't slide to the ground and also doesn't crush people.