we've had 2 5 tons do that to us this year, one looked like the pictures posted here, the other one shredded sidewall. our trucks sit quit a bit and the ctis leaks bad on some, my guess would be that ctis system leaked while sitting then the side wall gave out whining down the road. the tires didn't show any signs until they blew out.. both on the interstate... plus we had one engine failure. Pmcs can only get you so far, some days are just meant to suck...