I have a 2001 F150 with 50,000 miles on it. I am hearing a strange noise in the front end. It sounds like a wow-wow noise which is pretty loud at about 30 MPH. Thought it was a bad tire, have rotated tires three times with no change. I tried new wheel hubs and a front end alignment but the noise is still there. It does not get louder depending on which way I turn. Could it be a halfshaft or the front drive shaft. Nobody seems to have any idea and I am getting tired of throwing parts at it without results.

 

I know you have rotated the tires but your explanation of the noise sounds too me like a tire. Sometimes even when tires are rotated the noise can move with the bad tire and not really sound like it. Especially if the noise is pretty loud. You didn't mention any vibration. You have 50,000 miles on the truck and I suspect the same on the tires. I would inspect the tread wear and also for out of round on each tire. Maybe go to a tire store and have them check it out. Of course it could be a front end component as well. Some of the guys here have much more experience on those parts than I do and maybe can point you in the right direction. Good luck.

 

These actually are my second set of tires and that is a possibility that the tires are bad. As far as front end components I have replaced all the ball joints and all tie rod ends also installed new shocks. I am running out of parts to replace. There is only a very very small amount of vibration. Maybe I will contact my tire dealer and have them checked.