Mustang SSBC Rear Disc Brake Conversion (1987-1992) Installation Instructions
This Standard Rear Disc Brake Conversion Kit from SSBC fits every 1987-1992 Mustang.
This rear drum to disc brake conversion kit applies to 4 lug axles, and fits all four cylinder and eight cylinder Mustangs. It includes all hardware and a master cylinder. The rotors can come with optional turbo slotting and Xtra Life plating.
Tools Required:
- Wide Socket Set
- Pry Bar
- Scrapers
- Hammer
- Jack and Jack Stands
- Wrenches & Pipe Wrenches
- Brake Line Cutting Tool
- Flaring Tool
- Torque Wrench
- Drum Brake Tools
- Needle Nose Pliers
- Disc Brake Quite
- White Lithium Grease
- Vise on a Secure Table
- Drip Pan for Gear Oil and Brake Fluid
- Can of Bolt Loosener
- Power Tools, especially an Air Ratchet, are helpful
- A second person is helpful
Install Difficulty:
- Difficult Project
1. To begin the installation of your new Mustang SSBC A112-1 Rear Disc Brake Conversion Kit, jack up the car and support it with jack stands on all four corners.
2. Remove the drums and Mustang brake shoes. You might have to hammer the drums.
3. Remove the Mustang differential cover and drain the gear oil. After removing the bolts on the differential cover, tap a pry bar or scraper in between the cover and the differential to separate them and break the seal. Keep 1 bolt threaded halfway until it is completely drained. After the fluid is drained, remove the rest of the cover.
4. Find the pin and the bolt that keeps it in. To keep the gear from spinning, use your pry bar. Remove the bolt and the pin should drop out. Be careful to not let it fall into the drain pan.
5. After the pin is removed, push the axle shafts inward until you can't move them any further, which is about 1/2 inch. You should see the Mustang axle C-clips that retain them. Remove the clips with a pair of needle nose pliers.
6. Slide the Mustang axles out of the differential and set them aside.
7. Remove the brake line from the wheel cylinder. Mine was seized, so I just cut the line. No matter how you remove it, the stock line will be too long for the new brakes and need to be cut. See steps below for more details on that procedure.
8. Remove the backing plate for the Mustang brake drums. To do so, you will probably need to clean the bolts off. Then, just let them hang from the parking brake cable.
9. Open the hardware kit for the Mustang 4-Lug Rear Disc Brake Kit and separate the different kinds of bolts and hardware.
10. Install the splash shield to new backing plate.
11. Install the new backing plate with the nuts and bolts from the hardware kit. The heads are 14mm. Make sure the Mustang brake caliper is mounted towards the back.
12. Reinsert the axles, and put the C-Clips back inside, then pull the axles out. They should not move out more than an inch. Reinstall the pin and the retaining pin bolt.
13. Clean off the old gasket material on the differential and cover pan. After the old gasket is clean, apply new sealant or a new Mustang differential cover gasket and re-bolt the cover to the differential. You can refill the differential now, but it will be easier later when the drive shaft is out. This picture is of the new sealant after cleaning the gasket.
14. Put the new Mustang brake rotor on the axle, then bolt it down so it won’t wobble. My lug nuts were not deep enough to fit, so I used a 1/2 inch socket to fill the gap.
15. Install the caliper to the backing plate. You might need to install shims to make it line up. Shims are included with the kit, so all you need to do is put the shim in between the caliper and the backing plate. Once everything lines up, torque to 80 ft lbs. Make sure that the rotor turns around completely. If it does not, you need more shims.
16. Remove the caliper from the caliper bracket. Apply disc brake quite to the back of the brake pads.
17. Use a little bit of white lithium grease on the caliper bracket where the Mustang brake pads sit on the bracket, then install the pads.
18. Install the caliper back on the bracket.
19. Install the banjo fitting using 2 copper washers on each side, then torque to 25 ft lbs. Install the line that is included the hardware kit. It will most likely have to be bent so it will fit.
20. If you need to bend the Mustang brake hose, do it so that the 2 coupling ends are facing away from each other. Then, cut the brake lines down further and install a compression fitting, along with a bit of the new line. If you have or can get a tool that allows you to flare out the end of line, use that, or you can try to bend the existing line. If you didn’t cut it earlier, you can try to bend it around. Once you're done, use a brass fitting to connect the lines.
21. Bench bleed the new master cylinder. To do that, secure it in a vise, then install the hoses provided and loop them around to the reservoir. Fill the reservoir. Use a wooden or plastic dowel, or something similar, and push in on the master cylinder until the air bubbles completely disappear. It is recommended that this is done about 5 to 10 more times after the last air bubble disappears, just to make sure all of the air is out. If there is any air left in, it won't come out by bleeding the brakes, so you'll want to take some extra time here to avoid having to redo this step later.
22. Remove the old master cylinder and the lines connecting it to the distribution valve. Unbolt the 2 nuts from the brake booster. Remove the brake line from under the Mustang brake master cylinder, then remove the brake lines from the top of the distribution valve. If they’re seized, remove them from the side of the master cylinder, then cut the line and take a socket to them. Don't worry about keeping the old lines, as new ones are included in the kit. After the lines are off, remove the master cylinder. You can dump out the remaining brake fluid.
23. Put the new master cylinder on the Mustang brake booster and bolt it down using the same nuts. Install the new lines to the master cylinder and bend them into position to connect to the distribution valve. Do the back one first. Don’t tighten them down until they are all in place. The line that went into the bottom of the master cylinder will go in the bottom of the brass 3-way T fitting. Make sure the lines are not too close to the exhaust.
24. To remove the parking brake cables, first remove the console and the shifter bezel. The shifter bezel should just be clipped in. Next, remove the armrest. To do this, remove the two panels that are on the bottom part of the back of the console. Behind those covers are four bolts that need removed. The armrest will then slide up, revealing two screws on top of the console and two on each side. This allows you to disconnect the wires. These wires just need moved out of the way of the parking brake handle.
25. For the rest of the Mustang 4-Lug Rear Disc Brake Kit project, you'll need a second set of hands to help you. First, remove the Mustang drive shaft. There are 4 bolts that are 12mm 12 point and need removed. Before you do that, make sure the car is in gear (manual) or park (automatic) and have a friend hold the axle still by locking a big pry bar in the lug studs. After the bolts are removed, then slide the drive shaft out of the transmission and set it aside.
26. Pull back on the parking brake equalizer until your friend can slip a rod through the handbrake to hold the spring in place.
27. Remove the cables from the equalizer and feed the trough the turn wheel.
28. Remove the retaining clip from the floorboards and unbolt the only bolt on the cable attaching it to the floorboard.
29. To install the new Mustang parking brake cable, feed it back through the hole until the clip clicks. Then, feed back up through the turn wheel and back into the equalizer. Make sure you are using the side with the clip as they both look similar, but the other end does not have the clip.
30. Feed the other end of the cable through the hole in the caliper and into the spring on the back of the caliper. Then, with the new retainer and old bolts, bolt up the new cable to the floorboard. You will probably have to use a pry bar to lift the cable up to bolt it in.
31. Fill the differential with Mustang gear oil. Use a 3/8 inch socket to remove and tighten the bolt.
32. Pull back on the equalizer, then pull the pin from the handle and slowly release the equalizer. Then, test the parking brake. If they work, reinstall the drive shaft, the console and the rest of the interior.
33. Bleed the brakes. Start with the right rear and end with the left front. When bleeding the brakes, keep the reservoir covered as air pressure can cause the brake fluid to shoot up and cover everything in brake fluid that will destroy a car's paint. From here, test your brakes in a parking lot or another safe area, first at low speed, to make sure everything is working properly. This concludes your new Mustang SSBC Rear Disc Brake Conversion Kit install!
