Some 2014-2016 Lexus IS vehicles may exhibit a rattle-type noise from the rear of the vehicle when driving over bumps. This may require adjusting and cleaning/lubricating the parking brakes.
Adjust the parking brake per the repair manual. Make sure that the No. 1 wire adjusting nut is completely loose during parking brake adjustment. This will ensure that there is no gap between the shoe and anchor plate inside the parking brake assembly. If a gap is present, a rattle type noise may occur.
Road test the vehicle. If the noise is still present, remove the parking brake shoes and parking brake shoe lever sub-assembly.
Clean up the parking brake shoes, shoe lever sub-assembly and backing plate.
Apply disc brake grease to the areas of the parking brake plate that makes contact with the shoe and anchor block sub-assembly and reassemble. Road test to confirm the repair.
Apply disc brake grease to the areas of the parking brake plate that makes contact with the shoe and anchor block.