To help ensure that the correct tires are installed on Honda and Acura vehicles, American Honda dealers have tire replacement charts, called "Tire Fitment Guides." The "Tire Fitment Guides" list the correct replacement tire model numbers from various tire manufacturers (see Figure 2).

Figure 2 - This is an example of the front page from the American Honda Motors 2010 tire replacement chart. Subsequent pages include previous model year listings, going back to the 2000 model year.

Incorrect Tires May Affect Vehicle Performance
If mismatched tires are installed, either front-to-back or side-to-side, the tires may have different responses to certain situations. Mismatched tires may not perform predictably. For example, the 2009 Honda Accord sedan Owner's Manual states: "The anti-lock brake system (ABS) and vehicle stability assist (VSA) system work by comparing the speed of each wheel. Tire size and construction can affect wheel speed and may cause these systems to activate."

Additionally, tire differences may affect all-wheel-drive systems. The clutch that activates the all-wheel-drive system is activated by the difference in rotation speed, which could be affected by differences in tires.

Replacing in Pairs or Sets
When replacing tires, it may be necessary to replace tires in pairs, or the set of four to ensure proper vehicle handling and performance. For example, the 2009 Honda Accord sedan Owner's Manual states: "It is best to replace all four tires at the same time. If that is not possible or necessary, replace the two front tires or two rear tires as a pair. Replacing just one tire can seriously affect your vehicle's handling."

Tire Demonstration

To give you an idea of how two similar tires can react differently, watch the video demonstration showing how two tires of the same size and model compress differently when an equal amount of weight is applied to each.

The tire, manufacturer part number 0245-67, is specifically engineered for a Toyota Yaris, and showed less compression in the demonstration. The tire, manufacturer part number 0245-66, is specifically engineered for a Honda Fit, and showed more compression in the demonstration.

In the video demonstration, the tread construction on the tire showing more compression, tire number 0245-66, is 1 polyester ply and 2 steel plies, and the sidewall construction is 1 polyester ply. The tire showing less compression, tire number 0245-67, is the same with the addition of 1 polyamide ply in the tread construction.

Conclusion

If tires require replacement on Honda and Acura vehicles, always verify the manufacturer part number for replacement tires. Doing so will help to ensure that the correct tires are installed, and that no performance issues from installing incorrect tires will result.

This article first appeared in the October 11, 2010 edition of the I-CAR Advantage Online.