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Tips on Purchasing Tires

Tips on Purchasing Tires

Let’s face it.  The majority of us don’t pay attention to our tires until it’s too late.  Below are some tips on how to purchase your next set of tires.

⦁    Ensure you really do need new tires

Your tires may need to be changed if: there is excessive tread wear, cracked sidewalls, discoloration, or bulging.  If your tires are as old as 10 years, you should replace them even if they look ok.

⦁    Make sure your car is in decent shape.

You should inspect your tires for uneven wear.  This could mean an alignment or suspension issues.  You should get your alignment checked if you notice an uneven wear and get it fixed before you replace your tires.  Putting new tires on a misaligned vehicle is just throwing money away.

⦁    Review your owner’s manual and the information placard.

Each brand and model of vehicle has their own recommended size and type of tire for best performance.  This information is found in the owner’s manual.  The information placard is required by law to be placed permanently on your vehicle.  It can be found attached to your door edge, door post, glove compartment door or inside your trunk lid. 

⦁    Decode your tire code.

Tires all come with a code that is etched into the sidewall of them.  They are part of a standardized code.  Below is how to figure out what it means.

An example of a code could be P215/65R 15 95H M+S

The letter P indicates a passenger vehicle.  Another possible letter combination is LT for light trucks.

215, or any 3 digit number that follows the letter is the tire’s width in millimeters from sidewall edge to sidewall edge. 

The two digit number that is separated (in this case is 65) is the tire’s aspect ratio which is the height to width. 

The letter after the two digit number (in this case is R) indicates radial construction.  Only tires for a classic car may be different.

The next two digit number (in this case is 15) is the diameter of the wheel that the tire needs to fit.

The next two digit number (in this case is 95) is optional.  It may be three numbers.  It is the index number not required by law.  It corresponds with the tire’s load-carrying capacity.

The following letter (in this case is H) is the tire’s speed rating.  It is recommended to heed the manufacturer’s recommendation of speed rating.  An upgrade of speed rating is only recommended if you have upgraded your vehicle to a racing vehicle or plan on using a super highway, much like the Autobahn in Germany.

The final letters, stated either M+S or M/S, stand for mud and snow.

If you have any questions about which tires are proper for your vehicle, you should talk to your neighbourhood mechanic or a reputable tire center.

⦁    Take your wheels into consideration.

The rims should be considered to be replaced if your wheels are really worn or damaged.  Your newly purchased rims should be the same size as the last.  If you plan on buying larger rims, there are mathematical things to consider.  It is best to talk to your mechanic to see if your vehicle itself is a match for larger rims and wheels.

⦁    Purchase a full and matching set of tires.

Tires can be expensive, especially when purchasing 4 at the same time.  Yet, this may be the best bang for your buck.  Newer and modern vehicle suspension technology is designed to be the most efficient with a matching set of tires.  This will save you money on gas and repairs in the future.  It also improves your vehicle’s safety.

Fogelson, Jason (July 10, 2008). Buying Tires: 10 Great Tips.  AOL Autos.  Retrieved from

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