Ok...So i have a 2005 F-150 XLT Supercab 5.4L 4wheel drive. Occasionally there is a squealing coming from the front left suspension/tire. When i hit the brakes it stops. It doesn't squeal all the time but when it does it sounds like metal on metal. Is it the brake pad? Or do my joints need to be lubed up? Or is it something else. Only have 17,500 miles on the truck.