How To Buy The Correct New Tire

The tires installed on your car or truck when it was new had a Tire Performance Criteria Specification (TPC Spec) number on each tire's sidewall. This number ensures that the tire was built specifically for the vehicle they were installed on.

When you get new tires, We recommend that you get tires with that same TPC Spec number. That way your vehicle will continue to have tires that are designed to give proper endurance, handling, speed rating, load range, traction, ride and other things during normal service on your vehicle.

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If your tires have an all-season tread design, the TPC number will be followed by an MS (for mud and snow). If you ever replace your tires with those not having a TPC Spec number, make sure they are the same size, load range, speed rating and construction type (bias, bias-belted or radial) as your original tires.

Choosing A Different Tire Size

Many people like to change the tire size or model because they think they know enough about them to give better performance, tread life or just a better look. But, if you choose the wrong tire type or size you can easily degrade the performance of the your vehicle. After all, the tire is the only thing between your car and the road and will have a VERY BIG effect on the way it handles, fuel economy, speedometer accuracy and the general feel and sound of your vehiclecar or truck. Tire Sie Numbers Explained

A small change in tire size can have a big impact on fuel economy. Some people like the look of bigger tires, especially on trucks. But here is a good example-
A change from a common tire size of 235/65/R16 to 255/65/R16 will cause a speedometer reading error of 2.5 miles an hour at 60 MPH. The tire with 255 is a taller, larger circumference tire. At 70MPH on the speedometer the actual speed of your vehicle will be 62.5MPH. This will cause havoc on todays computer controlled vehicles, not just the speedometer being off, that is unless your get the computer reprogrammed to tell it the new tire size.

Not only will a taller tire effect mileage, it will also cause problems with outer edge wear, especially on trucks. When a vehicle is turning, the normal geometry of the front suspension causes the tire to tip a little. The top will tip outward or inward and the bottom will do the opposite depending on the direction of the turn. This will cause more wear than if the tire size was the original that the vehicle was designed with. There is a sticker on the inside of the drivers door that shows what the car was built with.

Changing Tire Pressure

Proper tire pressure is also very important. Changing tires pressure can also effect the handling of your car as well as the life of the tire. Suspension problems can occur with pressure that is too high or too low. See this link for examples of tire problems caused by under or over inflation.

Improper Tire Pressure Problems

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