Purchasing tires for your Jeep Cherokee is a much easier experience if you already know the size of the tire you need to purchase. According to tire information website tiretrack.com, the best and most popular tire for the Jeep Cherokee is size 225/70R16. These are not just random numbers.
Tires are classified according to type, and most tire sizes begin with a letter; for example, P225/50R16 91S. The "P" stands for "P-metric" size, which means the tires are designed to be used on passenger vehicles. P-metric tires are best for cars, minivans, sport utility vehicles and small pickup trucks. "T" means "temporary spare" or designed to be used as a spare tire. "LT" stands for "Light Truck-metric" when it's at the beginning of a size, which means the tires were designed for vehicles that do heavy pulling and towing, such as large pickup trucks, SUVs and vans. When a tire size ends in "LT," it means the tires are larger and designed to help a vehicle pull cargo or drive on loose, slippery surfaces. A "C" means the tire is designed for commercial purposes and "ST" designates "Special Trailer Service" size. When there is no letter at the start of the size, it means the tires are "Metric" size that are mainly used on European cars, but can also be used on vans and SUVs.
For the Jeep Cherokee, the standard tire size should begin with a "P" for a passenger vehicle—or should not have a letter listed.
The component of a tire size that comes after the initial letter signifies tire width. So for tires listed as P245/60R18, 245 indicates the width. This is the distance, in millimeters, from the tire's outer sidewall to its inner sidewall. A sidewall is the side of a tire from its tread to its rim. For a Jeep Cherokee, the ideal tire width is 225 mm.
The next number in a tire's size is a two-digit aspect ratio. This number measures the ratio of a tire's sidewall height to its section width. The higher the number, the taller the sidewall. A Jeep Cherokee should have an aspect ratio of 70.
The letter that follows the aspect ratio in a tire's size indicates the tire's internal construction. An "R" means that the tire has radial construction, meaning that the tire's body plies radiate out from the center of the wheel; a "B" means the tire has a belted construction, in which the body plies crisscross the tire and are reinforced with belts. Radial tires are the most common form today and the type a Jeep Cherokee takes.
The last number in a tire's size is a two-digit number that determines the size of the tire and wheel to be matched together. Rim diameters between 16 and 28 are measured in inches and are the most common type. Rim diameters between 390 and 415 are measured in millimeters and are not often used today. However, a wheel measured in inches must be matched with a tire measured in inches; same with the millimeter measurements. A Jeep Cherokee has a tire and wheel diameter of 16 inches.
