The job starts by jacking up the front end and placing the car on jackstands. I also stacked two wheels under the sides for additional protection should anything go wrong. I prefer working on a clean car and had washed it the day before, this is why the old rotors look stained. It is wise to do one side at a time in case you need to reference the other side. I advice you to replace the rotors when you are also replacing the pads anyway: If you keep half-worn pads, the wear ridges and grooves will inevitably be transferred to the new rotors.
(1) Here is the brake layout. The pads are held in position by the two horizontal guiding pins, which are secured by retaining clips and anti-rattle springs. Removal starts with pulling the clips...
(2) ...and continues with tapping out the pins. Before you do, note the position of the spring wires. I find it to be good practice to install the pins with their heads towards the centre of the car, as this makes them easier to remove should they get stuck. Beware: the springs will sometimes fly off when the first pin (or the punch) is pulled out.
(3) Gently press the pistons back in the caliper, but keep an eye on the brake fluid reservoir so you don't flood it. Some advice to open the bleeder valves to prevent old and contaminated fluid get pushed back up the line. In my case, I had completely flushed the brakes less than six months earlier. Now the old pads can be eased out. The anti-squeal shims (backing plate) will follow. Inspect the condition of the rubber seals surrounding the four caliper pistons and for fluid leaks in this area.
If you are replacing the pads only, jump to (8).
(4) At this point I removed the two bolts on the back of the caliper (19 mm socket, or 3/4") and tied the caliper to the spring with a piece of wire so it wouldn't hang by the brake lines. The two small bolts (10 mm socket, or 7/16") next to the hub are now off, and all that holds the rotor now is possible rust. I gave the rotor a couple of friendly knocks, and it came off. You might not be so lucky, this is where you might get frustrated. Keep knocking. A pry bar or large screwdriver could come in handy too. Also, it could be wise to do this in a different order than I did; to remove the rotor first, and then the caliper. That way it is easier to abort and take it to a shop if the rotors are stuck beyond removal with the tools you got.
(5) I cleaned the hub rim with a stiff nylon brush and a rag. This is the contact area between rotor and hub, and I wanted a clean fit. I also applied a thin film of copper paste, to make future removal easy. Any anti-seize product will do, as long as it is designed to stand up against hot temperatures.
(6) The new, original rotors from the Volvo dealer come with two new bolts for the caliper. The workshop manual strongly warns against re-using the old bolts! Also, original rotors are packed in plastic that gives off fumes that protect the steel from rust. This means that original rotors are not covered with oil or grease, and do not need any cleaning. Aftermarket parts may be different.
(7) Put the new rotor on the hub, remember the two small bolts, and mount the caliper. Torque to spec - 100 Nm. In my book, that means first torqueing both bolts to 80 Nm first, then to 100 Nm.
(8) I recommend getting the extra hardware kit with new pins, clips and springs, that is what is in the plastic bag. Original Volvo pads may make a lot of dust, but they do a very good job of stopping the car. Volvo pads come with anti-squeal shims.
(9) Apply copper paste or similar to one side of the anti-squeal shim and place it on the pads' backside. Apply more paste where the caliper pistons hit the pads/shims, this will make future removal easier. Take care not to get any paste on the pad surface, clean it off if you do. For cleaning brake dust, copper paste etc. from the parts, spray can cleaners like CRC's Bra-Kleen are excellent.
(10) With new and thicker rotors and pads, I needed to press the pistons even more back. At this point the brake fluid reservoir was so full that I put a plastic hose on a bleed valve and opened it (8 mm wrench) to let out about one deciliter in a cup. Install the pins, springs and clips. I smeared a thin film of copper paste on the pins' full length before installing: the pads will slide on these as they wear. When pushing the pins in place, rotate them so the holes for the retaining clips will face out.
(11) Mount the wheel, and enjoy the sight of shiny new brakes! Put the car on the ground, torque the lug nuts, start the engine, and pump the brakes a few time to build up pressure. Take the car for a careful test drive.