1995 Nissan Altima, 110k miles

I got my car checked recently and the mechanic told me that the car has a loose stab link. Just wanted to know what is it? Also, when I apply brakes there is a wierd sound that comes, like some rotating plate (tuck tuck tuck) and it stops when the car comes to a halt. Is it by any chance related to the loose stab link or it could be something more? I just had the brake pads changed day before.

Thank you for your help.