In a recent article in Road & Track they stated that it is crucial to keep close to the overall circumference of the original-equipment setup for tires so as not to affect things like speedometer input, stability and yaw management, traction control and ABS. They say while it's OK to change tire sizes, the rolling circumference (defined as the wheel size + twice the sidewall x 3.14(pi)) must be close to the original. For example a P225/060ZR-15 tire would have a rolling circumference of 80.4 inches. But if you went to a P245/50ZR-15 you get a rolling circumference of only 77.4 inches, some 4 percent less. However, going to a P245/50ZR-16 calculates out to a rolling circumference of 80.5 inches, only 0.1 greater than the original tires, which they say is no problem.

My question is: is this a problem with 5th gen Maximas? Other than the speedometer being a bit off, is this a valid consideration for our cars?

 

What size difference were you contemplating?

 

I would say yes. ABS would most likely be affected if you ran with upsize tires that were way off from the OEM rolling circumference.

 

I hadn't anything specific in mind. But I'll need new tires in the next month or so, and often the tire shops don't have the exact original size but say something like, "This size is different but will fit just fine." After reading the article, I don't know if that's good enough anymore.

 

Considering the fact that a good portion of factory speedo's have (if I remember from reading somewhere) around a 3-4% margin of error, I would say if you were looking at tire swaps close to or within that range it would be like stock anyway.