Rear disc brakes on 2006 ford 500 is tool required to compress brake cylinder?

Yes, you'll need a tool to compress the rear brake cylinder pistons on a 2006 Ford 500 to install new brake pads. A C-clamp or a specialized brake caliper piston compression tool is typically used. A C-clamp can work, but a dedicated tool is generally safer and less likely to damage the piston or caliper.