Class A Tires

I replace my 22.5" G670's at 10 years and they still look good. Some owners with money burning a hole in their pocket change them at 5-7 years.

The G670's have a 7 year warranty for cracking. Why replace before the warranty is up.

Virtually impossible to tell, as much of the "how long is their useful life" depends on how they were cared for.

Always properly inflated or run under-inflated/overloaded?
Store indoors or with tire covers, or left out in the sun?
Driven frequently, or sat for long periods of time?

Ah... not 08/11....but really the 8th week of 2011.

Typically, most of us start replacing around 5 - 7 years old. I would think you're ok for another year, but now is the time to start looking for a good deal.

Ron