Before you get started, thoroughly read
http://www.svo73mm.cjb.net/ if you have 5 lug wheels or rear disk brakes.
Quick and dirty brake pad change.
If you fluid isn’t excessively dirty or burnt smelling you can skip changing it for a simple pad replacement.
You need a T-45 Torx bit from the auto parts store to remove the front calipers.
You need a 6” iron C clamp to compress the pistons on the front brakes so you can put the new pads in. See Home Depot, Lowes or Ace Hardware for the C clamp.
You need front pads.
You said rear disks brakes – fox body Mustangs did not come stock with disk brakes with the exception of some SVO (5 lug, 85-86 models) and the 93 Cobra.
If you have 4 lug wheels and rear disk brakes, then you have a 87-88 T-Bird Turbo Coupe/93 Cobra rear axle (same basic axle assembly for both cars). The pistons for the rear disks screw back in and need a special tool that you can rent/ borrow from the auto parts store.
If you have 5 lug rear wheels and disk brakes: you have either a 94-95 Mustang rear brakes, a 85-86 SVO rear brakes or Lincoln MK VII rear brakes. All of the disk brake assemblies and pads are different from each other. The special tool used for the Turbo Coupe/93 Cobra rear disk brakes is probably also needed.
Note: the rear pads wear at a much slower rate than the front pads, so you might not need to change them. If you have ¼” or more pad friction material, you can put off replacing the rear pads.
Changing the front pads:
Jack up the front of the car and put jackstands under the car. Remove the front wheels and set them aside Keep track of the lug nuts and wheel locks. You can remove one or both wheels according to your jack/jackstand arrangement.
Loose the cap on the brake master cylinder and wrap several shop rags or paper towels around the filler neck.
Use the big C clamp to squeeze the pistons back into the caliper. If you don’t do this, you’ll not be able to get the calipers back on the rotors. The pads will stick out too far. This will force brake fluid back into the master cylinder.
If you neglected the shop rags around the master cylinder filler, brake fluid may overflow and make a mess. Pizza boxes are good to put under your car when you are working on it to catch overflow and loose parts.
Check the hoses and calipers for signs or damage and leaks, replace as needed. Check the rotors for scores, cracking or grooves. Replace or re-surface if any of these defects are present.
Changing the rear pads :
Jack up the rear of the car and put jackstands under the car. Remove the rear wheels and set them aside Keep track of the lug nuts and wheel locks. You can remove one or both wheels according to your jack/jackstand arrangement.
Remove the calipers and then remove the pads. Note the anti-rattle clips and how the pads fit. Do only one side at a time so you can use the other side as a reference on how the clips and pad fit together.
Use the special tool to retract the pistons back into the caliper. If you don’t do this, you’ll not be able to get the calipers back on the rotors. The pads will stick out too far.
Check the hoses and calipers for signs or damage and leaks, replace as needed. Check the rotors for scores, cracking or grooves. Replace or re-surface if any of these defects are present.
If you have to replace a caliper or brake line, here's a sure fire way to make brake bleeding simple.
Garden Sprayer Pressure Bake Bleeder
1 each pump type garden sprayer, 1 - 1 ½ gallon capacity (size doesn’t matter much, it just has to be cheap and small enough to be easy to work with)
6-10 feet 3/8” clear plastic tubing
1 each ¼” brass pipe tee
1 each ¼” pipe to 3/8: hose adapter
1 each pressure gauge 0-60 PSI or so – all you’ll ever need is 5- 10 PSI, so the gauge range doesn’t have to be high.
1 each large rubber stopper – this is the hard part to find. It may take some searching to find one that is a snug push fit to the inside of the filler port on the master cylinder. You can use silicone rubber to seal a brass fitting to an old master cylinder cap, but they tend to leak too much.
Home Depot or Lowes has some ¼” brass pipe stock that is continuously threaded in the electric lamp repair department, along with the brass nuts that go with it. This is better than a pipe nipple, since the nuts can be used to secure the pipe in the cap or stopper.
OR if you can’t find the threaded pipe stock,
1 each ¼” nipple, 1 ½”- 2” long
The rubber stopper needs a hole drilled in it for the ¼” pipe nipple or threaded pipe stock. After you drill the hole, use some silicone gasket sealer to seal the pipe nipple as you push it into the rubber stopper. If you used the threaded pipe stock, use the nuts to secure the stock into the stopper.
If you can’t find a suitable rubber stopper, an old master cylinder cap can be used. Drill a ½” hole in the center for the pipe fitting. Cut the brass pipe stock to about 1”- 1 ½” long, the exact length isn’t too important. Push it through the hole in the master cylinder cap and thread one nut on top of the pipe stock where it sticks though the cap. Put another nut on the other side of the cap to lock the pipe stock in place. Apply some silicone rubber gasket sealer to both sides and when it is dry, screw the ¼” pipe that sticks out of the top of the cap into the tee.
Remove the sprayer hose and wand from the garden sprayer. You may find it easier just to cut the sprayer hose off short and connect it to the 3/8” plastic tubing. The idea is that the 3/8” tubing connects to the pickup tube inside the sprayer in a reliable, leak proof fashion. Another alternative is to remove the spray nozzle from the end of the spray wand and connect the 3/8” tubing to the wand. This leaves the hand valve in place and may be useful to start/stop the flow of brake fluid.
The 3/8” plastic tubing connects to the pipe tee using a push on hose barb type adapter. The pipe tee has one port for the gauge, one for the 3/8” hose and the other to connect to the rubber stopper or master cylinder cap that you modified.
Fill the pump sprayer with a quart of brake fluid. Set the garden sprayer on the ground and screw the pump handle down tight, and pump until brake fluid fills the plastic tubing. Then put the modified stopper or master cylinder cap on the master cylinder and pump slowly to make sure that nothing leaks or pops loose. No leaks, continue pumping until you get 5-10 PSI. Put a 6”-12” length of clear plastic tubing on the bleeder ports. Then open the bleeder ports on the wheel cylinders one at a time and bleed until the bubbles are gone. I use a 2 liter soda bottle with a coat hanger to catch the fluid . DO NOT REUSE THE OLD BRAKE FLUID. Repeat the process until you have finished all 4 wheels. You will have to pump the sprayer several times to maintain the 5-10 PSI needed to do the job. When finished bleeding, loosen the pump handle to relieve the pressure, remove the stopper/modified master cylinder cap and test the pedal.