2006 Ford Ranger Thumping Noise at low speeds

The tires look fine; I don't see any belts shifted. I can't tell if I am missing any wheel weights. Turning does not affect the noise. I just road around with a mechanic from the local Ford dealership( where I bought the truck new) so he could hear what I was refering to. He could definately hear it at 30mph but couldn't tell exactly where it was coming from. I am leaving it with them tomorrow(Wed. 13th) so they can find it. I'll let you know what they say.

I just got the diagnosis from the dealer mechanic about my low speed thumping noise. As you had suspected; it was a front tire wearing ununiformly causing the thumping. He recommended a tire rotation which put the problem tire at the rear. He said that initially there will still be some noise but will eventually go away as the tire wears down. Thanks for your response; I think your diagnosis was right on the money; especially not being able to see the vehicle and just going off my description of the problem!