I have just put PBR ULT's on the rear of my 525iT and despite Permatex on the mating surfaces of the caliper and outer pad, and the piston and inner pad, I still get a nice loud squeal on light braking, though better since I cleaned things up really well and reapplied it, but still annoying. Should I expect better results with brake lube instead? What is the consensus? Thanks very much.