I am not going to jump on your case but this is the wrong forum section for this question. This is the Mazdaspeed Protege threads. I am sure the moderator will move it shortly to the proper area, no harm done.
Can you describe the sound a little more. Is it a screeching grinding sound or simply put, a whislte sound? Any chance you can get a video with the noise or perhaps a sound byte? Can it be heard outside the truck or literally it is coming from beneath the pedal? What year and engine size, 4 or 6, manual or auto?