Difference Between Full Sized and Compact Spare Tires

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So you want to equip your vehicle with a spare tire, but don’t know which route to take. Both full sized and compact/donut spare tires have their positive and negative aspects that need to be taken into account when you are thinking of purchasing a new spare tire.

Today, we will take a look at what these tires offer in a bit more detail.

Tire Size and Construction

The first important factor to consider is the size of the tires.

Like their name suggests, full sized spare tires are the same size as the rest of the tires on your vehicle. These tires are able to perform in the same manner as regular tires can, as they are basically the fifth tire in the set. However, compact spare tires come in smaller sizes. They are manufactured in smaller sizes and with lighter weight to lower the space they take up in the trunks. Unfortunately, this results in them not being able to perform as full sized spare tires can.

While full sized spare tires offer excellent durability, compact or donut tires lack the structure necessary to perform at high speeds or with heavy loads. The internal structure of compact spare tires is lightweight, limiting their performance. Most donut tires are able to perform at 50 mph for 50 miles without issues arising, but any more than that can lead to tire failure.

However, the lightweight construction and smaller size make compact spare tires… compact. This minimizes the trunk space they take up and lowers the load pressure they put on the vehicle.

Traction and Performance

A tire’s performing traction is also an important issue to consider.

Full sized spare tires feature the same tread pattern as the rest of the tires mounted on the vehicle. This ensures their performing safety in versatile weather conditions. Compact tires on the other hand are unable to provide the same amount of traction. Their tread designs do not perform well once the weather turns foul. Driving on donut tires in bad weather conditions will be a tricky, and sometimes dangerous, decision.

Durability and Speed

Once again, looking at the internal structure of full sized and donut spare tires, we can clearly see a difference.

Full sized tires feature reinforced constructions, the same as the rest of the tires mounted on the vehicle. As a result, such tires are capable of securely performing in the same conditions as the other tires. This means that these tires will maintain their ideal shape under the load and driving pressure affecting the tires, without deforming during their performance.

On the other hand, compact spare tires sport a lightweight structure. This decreases the tire’s pressure durability and any added stress can lead to the tire’s deformation. Such tires MUST be used in accordance with their intended purpose, as stronger load or speed pressure, which affect the tire during their performance, will cause tire failure.

Conclusion

Whether donut or full sized tires are the correct answer depends entirely on your vehicle. The above mentioned factors can dampen the vehicle’s performance. Before choosing a spare tire, be sure to check a few things.

First of all, does your vehicle have sufficient trunk spare to store a spare tire or does it have any place to hold the spare tire other than the trunk? Full sized spare tires take up a larger portion of trunk space, while compact tires are manufactured to minimize the space they take up in the vehicle and may even have their own compartment.

Secondly, how do you want your vehicle to perform once the spare tire is mounted? If the answer is: the same as before, you may need to purchase a fifth tire which matches the rest on the vehicle for it to be able to securely perform at the same speed and load as your previous, damaged tire. However, if you are only looking for a temporary fix, something just to get you home or to a nearby garage, a donut spare might be a better option.

Thirdly, what weather conditions prevail in your living area? As we have stated before, foul and unpredictable weather will be hard for compact spare tires to conquer, which can lead to further accidents. If your area has unpredictable weather, and your car space allows it, it might be better to invest in full sized spare tires.

All in all, both full sized and compact spare tires perform well in their intended applications, but donut tires have their limitations, which might not be desirable for some drivers. On the bright side, they will maximize your trunk space if you opt for them.