Some vehicles may exhibit a groan noise from the rear brakes during braking. This applies to 2007-2010 CX-7 and CX-9 vehicles.
According to Mazda, the repair involves replacing the rear disc pads with modified versions. The modified rear disc pad set includes new brake pads, shims and guide plates (B). Prior to installing the modified pads, lightly and evenly apply white grease to the disc pads in the locations shown (C) (backing plate ears). Use care not to contaminate the pad or rotor friction surfaces.
The modified rear brake pad set is available as Mazda P/N L2Y8-26-43Z.