I have a 96 discovery and sometime while driving, it will make a whistling sound from the front left end? I do have a bad serpentine belt but that makes its own sound, could it be causing this sound to? As for the break when i put them on they make a click sound that i can hear and feel, whats that?

 

when was the last time you had brakes and rotors put on your truck? Is your ABS light on? Did you check your brake fluid level?

 

The pulsing that you feel in the brake pedal and the rapid clicking that you hear under the dash is the ABS module.
Open the hood, find the fuse box, remove the fuse to the ABS pump, that problem is solved.

As for the other, have your wheel bearings checked out TODAY!

 

the abs fuse is pulled already and as for the wheel bearings i will but what could happen if they are bad?

 

If you wheel bearings are bad then they will be noisy, then they will will eventually seize and then you are into some serious $$$.

Have your wheel bearings checked out, but it sounds like your rotors are warped and you need new brake pads and rotors.