What makes a spare tire different?
Spare tires come in all different types depending on the what the manufacturer felt was necessary for the design of the vehicle. Your spare tire may be the most common type, which is a space-saver spare. There are also collapsible spares, full size spares, and tire repair kits that are used in place of a spare tire. Depending on which type of spare you have will determine how the tire is constructed and how it must be used should you ever find yourself in a situation that requires you to use your spare.
We can start with the tire repair kit. This kit has nothing to do with the tire itself as it consists of a tire sealant, such as fix-a-flat, which can inflate and seal the tire for a period of time so that it can be driven on.
A full size spare is generally a regular tire that is used at the spare. If you have a full size spare you can typically use this just like any other tire as it carries the same construction as the tires on your car.
Space savers and collapsible spares are different. These are the most common types of spares used on cars. These spare tires are made to be smaller and lighter than the tires that come on the vehicle. This is done because it reduces the amount of space needed for the spare, and the reduced weight can assist in vehicle fuel mileage. These tires come with a reduced amount of tread on the tire which reduces the weight and space that is needed to store the tire. This make it to where the tire should only be used for a short period of time, typically less than fifty miles. The space saver and collapsible spares will also have a different inner construction. By this, the tire does not have the same type and amount of internal steel belts. Radial tires are designed with steel belts of all different types. The type and amount of steel belts will affect the longevity of the tire as well as the strength and durability of the tire. The downfall of multiple steel belts is that it adds extra weight to the tire. Since space saving spares are designed to be lighter and take up less space they will not have the same amount of steel belts as the tires used on the vehicle every day. This also will affect the way that the spare is used. This is why these tires have a speed limit on them. The lack of steel belts keeps the tire from maintaining its shape at higher speed, so that is why they usually have a 55 mph cap on their use.
Besides the usual inspections that you must do to maintain a spare tire, you may want to upgrade it at some point depending on your situation. If you have a roadside assistance service you may never need to use your spare. If you drive your vehicle long distances and find yourself in rural and desolate areas then you may want to upgrade your tire to a full size spare. You can purchase a full size spare tire and wheel at most tire stores. This will give you the benefit being able to still drive your vehicle at normal highway speeds should you ever need to use it, and you will not be held to a limited driving distance.
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