Great video never knew one could find the year tire was made. I also need 4 new tires for just this reason age cracks while the tread looks VG the tires do show rot. I am going to replace the tires but want a tire that will be better in the sand than the regular radial tires any suggestions. I wonder what precautions can be taken to try and eliminate this cracking? any treatment that can be applied? I know I cover my trailer tires to avoid sun damage I am wondering if the sun can contribute to this cracking on car tires. I have had one of the tires that show cracking and there is no evidence on the inside of the tire could the cracks be superficial or sort of a cosmetic thing? Lou
UV light can damage tires, but "dry rot" is not due to vaporization of chemicals from the tires, as suggested. It is actually from air pollution--ozone anyway. Rubber and synthetic rubber are organic compounds--polymers--essentially long chains of elements to make one molecule.
For sake of argument and without further explanation, these molecules have three kinds of bonds holding together the individual elements of the molecule (single, double and triple). The cracks are are not a physical change because of evaporation as stated; but, a chemical change in that double bonds within molecules of tire are broken.
This was just FYI about "dry rot." (If you really need to know more, do some looking into ozonolysis.)
UV, ozone and polymers: fishing line.