The Audi TT is equipped with a brake caliper and a brake rotor system on both the front and rear wheels. The brake pads are housed inside the brake caliper and compress to the brake rotor to stop the vehicle. When you press the brake pedal, the brake pads push against the rotors. The friction from the pads sliding against the rotors brings your Audi to a safe stop. You should always change the brake pads before the pad thickness reaches 1/8 inch.
Park the Audi TT on a flat surface and set the parking brake. Turn the engine off.
Loosen all of the lug nuts on the front wheels about a 1/4 turn counterclockwise, using a tire tool.
Jack the front end of the Audi TT up and place the jack stands under the proper front jacking points. Lower the car onto the top of the stands.
Finish removing the lug nuts from the front wheels. Pull the front wheels off and place the wheels in a flat position on the surface. Begin the brake pad replacement process on the front driver's side of the Audi TT.
Locate the two upper and lower metric mounting bolts on the back side of the brake caliper. Loosen and remove the bolts with a ratchet and a metric socket. Slide a flathead screwdriver between the brake rotor and the outboard brake pad on the back side of the rotor. Pry the brake pad back and forth until there is enough slack in the caliper to remove it from the rotor.
Slide the caliper off of the rotor and hang it on the front coil spring behind the wheel hub assembly with a bungee cord. Pull the inboard brake pad out of the front side of the brake caliper. Position the C-clamp around the back side of the caliper and the front of the outboard brake pad. Compress the brake pad with the C-clamp until the caliper piston is fully retracted inside the caliper. Remove the C-clamp and the brake pad from the caliper.
Slide the two new brake pads into each side of the brake caliper. Inspect the brake rotor for any damage, such as excessive grooving or excessive wear. If the damage is excessive, replace the rotor. If the damage is minimal, have the rotor turned by a machine shop or an auto repair shop. If there is no damage to the rotor, leave the rotor in place.
Remove the bungee cord from the brake caliper and slide the caliper back over the rotor and onto the caliper mount. Screw the mounting bolts back through the rear of the caliper. Tighten the caliper bolts with the ratchet and socket. Tighten the caliper bolts to 25 foot-pounds, using a torque wrench and a metric socket.
Slide the wheel back onto the hub and screw the lug nuts on tight. Move to the other three wheels and repeat the brake pad replacement process. When finished with the brake job, raise the Audi TT above the jack stands. Remove the stands and lower the car back to the surface. Remove the jack.
Finish tightening the lug nuts very tight with the tire tool. Crank the engine and push the brake pedal in and out a couple of times to position the new brake pads to the proper distance from the sides of the brake rotors. Test-drive the car in a safe area to check the operation of the new brake pads. Park the car and turn the engine off.
Most auto repair and machine shops will machine brake rotors to remove any damage.
Never install new brake pads with worn or grooved brake rotors. This will result in dangerous and uneven braking that can result in the brakes not working properly.