Q: Do I need a special tool to change the rear brakes on a 2004 Cadillac Deville?

The only special tool that is really needed is a caliper piston return tool. You can watch a good YouTube video on this here.

This tool comes in several forms and most are available for rent from your local parts store. Aside from this tool, you will need some sockets, a 3/8 drive ratchet, and 1/2 drive ratchet. The 1/2 drive ratchet will be necessary to break loose the larger bolts holding the caliper bracket in place. You will need to remove the bracket in order to remove the rotors for turning or replacement.

Be sure to have some high temperature brake grease for the caliper slides and any points where the pads contact the caliper. A can of break clean is necessary to remove the shipping grease that new rotors come covered in to stop rusting.

That should be all you need.

Good luck.