Often when choosing new tires and wheels for your car or truck the first factor that comes to mind is how they will look, and if the size you want will fit your vehicle. However there are many other factors that should be considered. Some of these others are how they will affect the performance of the vehicle, the road conditions that you will encounter, will a change in hight affect the safety of the vehicle, even will your speedometer still be accurate after the change?

Sidewall information
While researching for this post I came across a few other things you should be consider, like the age of the tire, tires do have a shelf life. In as little a 6 years the rubber can start to deteriorate, check the tire before they install it. You can find the DOT code on the side of the tire indicating it’s manufacturing date.

If you live in areas of more extreme temperature (Like the Redding heat), it’s good to check how well the tire will withstand heat buildup. With “A” being the highest rating and “C” being the lowest.

Does the warranty (in miles) stated by the tire company match the rating on the tire. Just because the company states they will warranty the tire for 60,000 miles does not mean you will actually get the 60,000 miles, often the restrictions keep this from becoming reality. There is a tread-wear rating on the side of the tire that give a comparative rating of how long the tire is expected to last. Note though that this comparison is only good within a manufacturers product line. It is not valid for comparisons between manufacturers.

I’ve only touched the surface on the information you can find on the side wall. One of the better articles I’ve found on the subject is at carbibles.com, in this article on Decoding the sidewall information.

Tire size and the speedometer
Changing your tire and wheel size will also have an effect on the accuracy of your speedometer. In some cases this affect can be dramatic. Kouki.com has an interesting tool that can help you estimate how far off your speedometer will be with your new choice in tire and wheel. If your a little confused after reading the the sidewall as to how much bigger the combination will really be than the stock tires check out this Tire size calculator.

While you can always just take the chance that the person behind the counter really knows what they are talking about. With a little research you can be sure that the tires and wheels you buy will really be the best choice for you and your car.