A couple years ago, on the news, I listened to a story about how its possible to receive a set of new,radial tires that have been waiting on the shelf for some time. In some cases 6+ year old tires were being mounted. I know that radial age can be determined by a marking code on the tire. For Reproduction Bias Ply tires is it easy to determine the age. Does any one check age on their..cokers?. Any one have any links to information about this. What is a safe shelf life for a bias ply tire? 4-5 years?