I just bought a black `99 F 150 extened cab 4.6 off road 33,000 miles I have put 400 on it since, and have noticed a thump,thump ect.. which feels like a lump in one of the tires I think the front. it has what I think are the stock Good year wranglers 17" off road with good tread life but the out side edge **** have an angle wear on the leading edge of them. Is that normal for all terrain tires and the dealer said the tires were feathered and that feeling is a characteristic of those type of tires I told him I didn't think so beacause it feels like it is comeing from one point and not an all around feeling there going to rotate the tires next week but the tires on the back look the same so I have a feeling that it may not help if it doesn,t can some one tell me what to look for or what that feeling could be? and if I stick to my guns may be they will put on new tires But I also do not want to mask the the real problem if there is one.Thanks, Troy