should i be worried about this?
As a technician, YES. that usually happens when a tire is run with low psi. the side wall is stressed and starts to crack. That would actually fail NH state inspection. This doesnt' mean its going to blow out on you today, however i would take it easy on the car until your new tires come in.
yea man... dry rot isnt good. side wall isnt as firm...more likely to get a bubble or simply pop. doesnt look like you have that much tread on your tires anyway... so i suggest TIRE SHOPPING MEET FTMFW!!!!







