Front Suspension problems of the 1996 Ford E-350

As we were enroute to disney world with 2 adults and 2 children in the motorhome, we noticed a vibration that grew in intensity as we approached datona beach late in the afternoon. Within 5 miles of first noticing the vibration, we pulled off interstate 95 and I looked at all of the tires. As a former factory service rep for Ford and a fully certified ase mechanic from many years ago, I scrutinized the tires intensely with my eyes and hands finding nothing abnormal. We decided to press on to daytona beach to find a tire store and have the vibration checked out. Within 1 mile of pulling onto the freeway again, the front right tire shredded and damaged the undercarriage and fender paint on the vehicle. We summonsed a service truck and had the spare tire replaced. While in orlando, we ordered a new tire and had it replaced. Returning home we stopped at a weigh station to see just how heavy the vehicle was with just the four of us in it and found that we were within 300# of the max gross weight allowed for the front tires. The tire pressures have been maintained closely and the vehicle has been aligned regularly. There was now abnormal wear patterns on the tire. Last fall, the front tires were rotated with the inside rear tires to maintain the rotation pattern. ( dot number: vd1l1xa086 tire size: lt22575r16 ).