Remember a key factor is obtaining the mfg date coding, and checking it on the tires you are purchasing. Just because your buying a 'new' tire doesn't mean it hasn't been baking in various warehouses for several years. Generaly tire companies count the life of the tire from the date of manufacture with a 3 year lifespan on a tire as the tire dries out. I learned this the hard way. I purchased new tire for a truck I had, a month and a half later the tread seperated on the left rear and did major damage to the bedside. I called the tire company and told them their brand new tire failed causing damage. They had me read them the code of the tire and told me the tire was over 5 years old and was consideed worn out. Had it been under 3 years tey would hae fixed my bedside. So my brand new tire was worn out before it even hit the rim.