I'm sure you guys have seen/heard accurately, meaning the 5 year suggestion, but I'm always suspicious of time only guidelines on something like this. Does that mean 5 years from date of manufacture? If so, does that mean if you buy a tire that's not a hot mover and sits in a tire stores warehouse for a couple years you only get 3 years of calendar life? Or does exposure to sun, rolling friction heat cycles have more to do with life limits? If the latter does that mean an infrequently used car, such as a hot rod, that remains indoors away from UV issues much of it's life, would then have a longer calendar life? Is 5 years an average so that someone in Arizona has less tire survival life than a car up here in Seattle where it has less than half as much exposure to sunlight? I don't care much for limits based on time rather than environmental/use conditions...............sounds too much like a sales motivator than a quality/product life concern. I'm not much for conspiracy theories, but did this suggestion result from tire life going from something like 10-15k miles 40 years ago, to now we expect 50-60k miles regularly?