Rear Rotors
2. With the car safely supported on jack stands, proceed to remove the wheel nuts.
4. Before the last of the bolts is removed, the caliper must be supported
by a wire around it to the strut above - it must not be allowed to hang on the
brake line even momentarily.
5. With the caliper out of the way the rotor is exposed and may be removed
by inserting an M8 bolt into the pre-tapped hole in the rotor. If your rotors
have no such hole, then use a rubber hammer on the back of the rotor to dislodge it.
6. If the new rotor is wider than the old, then the pads must be removed and
the rear caliper piston pulled in by removing the 12mm hex-bolt on the back
of the caliper, exposing a 4mm hex socket-head bolt which is turned to move
the pads back away from the rotor. Do not back the pads off too far, otherwise
the bolt may come out causing brake fluid to leak. Never use a C-Clamp on the
rear caliper as it will destroy it.
When fitting the new rotor, use an anti-seize compound on the mating
surfaces of the hub & rotor to ease rotal removeal in the future. A typical
anti-seize compound is copper high-temperature anti-seize grease. Keep any
off the braking surfaces.
7. Caliper refitting is via relocating it & the bracket over the holes in
the hub plate and pushing the caliper down over the rotor. Do not damage
the piston boot. The caliper bracket mounting bolts should be torqued to
78-102Nm or 58-74lb/ft.
Last Upload: 31st January, 2002. V1.50a
Tools Required
Wheel removal sockets (19mm or 21mm), breaker bar, 13 & 17mm socket,
rubber hammer, pozidrive/philips screwdriver, torque wrench, copper
high-temp antiseize grease or similar. Hydraulic jack and U-top (not
V-top) safety jack stands. M8 bolt & matching socket. 4mm allen key.
Piece of steel wire strong enough to hold weight of calliper & bracket.
C-Clamp and piece of wood. Some cars may require a 5/8" socket and
7mm allen key.
Brake Rotor/Disc Min Thickness
The replacement thickness of the rear brake disc is 10mm (new is 8mm)
with runout 0.1mm maximum. Replace rotors across the axle. Rotor thickness
is measured using a vernier caliper at several points around the disc and
at several positions out from the centre/center of the rotor.
Rear Brake Rotors
US: Trussville Mazda (www.trussvillemazda.com)
do rear rotors discounted for ~40$US.
Jack up car & remove wheel(s)
1. Ensure the handbrake is on firmly, the car is level and in Gear/Park.
Chock the front wheels securely at the rear. Jack up front of car using a
hydraulic jack & support on stands at the proper Jacking & Support Points.
Removing calipers from hub
3. Rotor removal first requires the calipers & their bracket to be removed
from the hub. To remove the caliper locate the two 17mm bolts to the hub
bracket.
Re-Adjusting Rear Caliper
8. The rear caliper must be adjusted once the caliper is refitted.
Re-adjustment is by rotating the hex-key in the rear of the caliper until
the brake pads just contact the rotor, then back them off 1/3 of a turn.
Bleeding brakes
9. The brakes should now be bled ideally to eliminate any air or
moisture which has got into the system. See the Brake Bleeding
& Brake Fluid Change section for the procedure.
Finishing off
10. Then refit the wheel, putting a small amount of copper antiseize grease on
the hub-wheel interface. Retorque wheel lug-nuts in a 1-3-5-2-4 pattern
first to 50lb/ft then 80lb/ft to ensure even load and reduce chance of
rotor warpage.
Torque Figures:
Caliper Bracket mounting bolts torque: 78-102Nm or 58-74lb/ft.
Wheel Lug Nut torque: 80lb/ft.
URL http://homepage.ntlworld.com/dorothy.bradbury/probemx/p_m7.htm