Unless you drive one of the select few vehicles that are equipped with a full-size matching spare tire, your spare tire is not the same as the other four that are on your vehicle. There are significant manufacturing differences that make it clear that your spare tire is for temporary short-term use only.
The tire is a different overall height and width
Your spare tire, be it a full-size non-matching spare tire or a compact spare, is typically a smaller diameter than your four normal use tires. It may be a slight half-inch up to a couple inches in diameter different and the width is usually significantly less than your factory tires. This is to save space in your vehicle when the spare tire is stored.
The wheel or rim is made of lightweight material
The structure of the spare tire rim is less important than regular use rims, so it may have a much different wheel offset, or may even be made of lightweight steel compared to normal wheels. Being smaller and made of lightweight material makes it easier to install when necessary but also not usually as rigid or capable of the same abuse a normal wheel receives on the road.
The tread depth is much shallower
Because it is designed for use strictly in emergency situations, your spare tire will have very little tread and only a few sipes in the tread. It is meant to get you to a safe location or perhaps to a tire repair facility and not for everyday or long-term use.
Spare tires are not meant for everyday use, no matter if they are a full-size spare or a compact space saver spare tire. Have your regular use tire repaired and re-installed as soon as possible.
This article originally appeared on YourMechanic.com as How Do Spare Tires Differ From Regular Tires? and was authored by Jason Unrau.