Anyone else's Toyo sidewalls cracking?

These are Open Country A/T IIs but not sure if others experience the same thing. Granted, these are fairly "old" in my book, almost 4 years and ~40k miles, but still technically under warranty.

 

those look dry rotted to me thats why they are cracking.

 

Look at the date on the tire. I bet they are well over 4.

4 year old tires (any type) are about due for replacement anyway, regardless of tread left. The compound has hardened and the grip that the tire had for the first couple of years, based on the compound technology (not the tread pattern) is gone.