Had the 4runner in for oil change and inspection today at the dealer. (Free coupons...) Asked them to check out my rear brakes because they've been making noise. It happens after braking hard. It's not during the hard braking, but AFTER. Each time after that hard brake if I brake Softly or slowly,my rear brakes make a groaning noise as I slowly stop, like they are wet or slipping or something. Dealer checked the brakes and said they are fine and I notice no loss of braking power or anything. Service rep told me it's because of the material Toyota has been using on their brake pads,it's a common issue. Is that true or B/S? Had the truck since September and this problem didn't surface until about a month ago.