Squeek From Front Left Tire Area
 

Hello,
I have a 2000 Blazer 4X4 LS. I have been getting a squeaking sound (from I believe my left driver side tire) every once in a while after I drive over a pump and it will continue to squeak, then randomly stop. Then after I go over another bump it will start up again. The sound stays continuous with the motion of my tires. However, (as I discovered today) when the tire is squeaking and I apply the brake the pitch in the squeak changes. I know I still have plenty of brake pads left, so I'm not sure what the problem is. Can anyone help?