Only happens coming from a stop up to about five or ten miles an hour then it stops. Im thinking my rotors may be warped. I changed the brake pads before I drove to Florida but not the rotors. They are original and probably need changing any way. They do have grooves in them I will get pics. I drove the truck straight through Tennessee(mountains and stuff right) about a week ago but don't recall riding the brakes or anything all the way down.

 

How many miles are on the truck? It is probably time to get new rotors.