what kind of wear on the edges, from what you descibe, I bet you have high and low spots on the edges. If you do your camber is off on the alignment..go get it checked. It should be done every 6 months or 6,000 miles anyway. Go somewhere like firestone, etc that can sell you a lifetime alignment, they are a little more expensive, but you will save your hoops. If your tires have this wear, they will need to be replaced to remove the vibration.
69 x-11..LS1, 420.88 horse to the tires,750 Holley Ultra DP, Torquer V2, darksides headers, PRC heads, 10.8:1 compression, forged bottom end, 5 speed. 2008 King Ranch F150 4x4.