Determine the exact wheel specifications for your Jeep by using a tire website such as Wheel-Size.com to search by model and year for the correct tire and rim information. For 1987 to 2016 Jeep Wranglers, tire sizes range from 205/75R15 to 265/45R20 depending on the year, while 1974 to 2016 Jeep Cherokees have a tire size range of 215/75R15 to 275/40R20. The site should also list the correct bolt pattern and offset for your rims.
The side of a tire lists valuable information about that specific unit using a simple code. For instance, if your Jeep Wrangler needs a 265/45R20 tire, you need a tire with a section width of 265 millimeters, a 45 aspect ratio, radial construction and a 20-inch rim diameter.
A bolt number pattern specifies the number of mounting holes and the space between them that a new rim requires to fit your Jeep. For example, some Jeep Cherokees have a bolt pattern of 5x110. This number means there are five mounting holes with 110 millimeters between them when measured diagonally.
The wheel offset is the distance between the centerline of the wheel and hub mounting surface. Factory rims usually have a positive offset. For example, for 1974 to 2016 Jeep Cherokees that had 5x110 rims, the offset varied between 29 to 41 millimeters.