Mustang PBR Dual Piston Caliper Install
(From '99 Mustang Hardware)
This page outlines the installation of the factory Aluminum dual piston PBR calipers found on '99-'01 Mustangs onto a Thunderbird (Cougar) with '93-'97 Spindles. Information I have found points out that the MN12 brakes were derived from Sable/Taurus platform with their 10.87" diameter rotor. Subsequently the SN95 Mustangs adapted MN12 style front spindles and brakes. SN95s up until '98 used a similar single piston steel caliper using the same rotor with different bolt circle. In '99-'00 the stock brakes were changed to PBR (Australian Company) dual piston aluminum calipers. For a complete Mustang makeover you can actually put Mustang Hubs on MN12 spindles and use Mustang rotors with 4.5" bolts circle.
Disclaimer: This modification is offered here as a non-factory suppliment and should be employed with the knowledge that braking performance may be altered and that all necessary safety precautions be taken.
This information is similar to the KVR Dual Piston upgrade found at the TCCoA. Thanks to those guys who helped with tidbits of info to make this article clean.
What you need: 2-Mustang Caliper Bracket, 2-Mustang Aluminum Calipers, 4-Caliper to bracket bolts, 4-Replacement Crush Washers, Set ofMustang Pads, 2-Mustang Banjo Bolts, 2-T-Bird rotors, Adequate DOT brake fluid, 3/8"x2' long rubber tubing.
Tools: Metric Socket set, hacksaw or grinder, jack stands, rags and brake cleaner.
Here is a comparison of the two different pads. The MN12 (T-Bird) is on the bottom. The top Mustang pad size is larger and provides better heat dissipation and less heat generation due to its larger size. If you cut and overlay the smaller pad over the bigger one in a picture editor it is more noticable.
Procedure:
1) After acquiring the needed parts, loosen the lug nuts on your wheels.
2) Raise the car and block it using the proper supports.
3) Remove one caliper at a time. The caliper is held onto the spindle via a bracket. Two bolts may be accessed from behind the bracket. I believe they are 15mm socket size. Support the caliper/bracket assembly while removing the factory flex hose and hose mount from the fender skirt mount. A plug or other temporary item should be used to prevent the fluid from draining.
CAUTION: If equipped with Anti-Lock Braking System, allowing the system to run dry will require a factory type brake bleed procedure to ensure no air has entered the system.
4) Take the Caliper assy with its hose still attached to the workbench. Remove the banjo bolt holding the hose mounting block to the caliper and set aside the hose for reinstallation.
4.1) There is a slight clearance problem on the top of the PBR caliper at the spindle. You must remove a slight amount of material from both the caliper and the spindle for the best results. Remove approximately .032" from the area circled in white. Temporarily hold the caliper in place and mark the area of closest contact.
5) Once removed I noticed that the hose mounting block was configured differently. You must modify the hose block or the Mustang caliper to use the MN12 hose. The Mustang hose fitting for the brake line is different thread and style of connection and would require the modification of the line's end to mate.Note: It is possible that by swapping hoses driver to passenger and vice versa, this can be avoided. Check it out and let me know.
Shown below is the factory hose for the Mustang installed on the Mustang PBR caliper. Notice the top of the mounting block rests very close to the edge of the machined shoulder of the caliper.
The picture above shows that the top of the MN12 mounting block interferes with the machined shoulder of the caliper. The block's hole is offset the opposite direction from the Mustang factory hose. Clearance can be provided by either cutting the block just inside of the shoulder dimension or carve a bit of the shoulder away to clear the block. End item picture of the carved out shoulder boss is shown below. Care must be taken not to gouge the mounting surface of the crush washer for sealing. This configuration prevents the block from rotating and loosening the hose mount.
6) Clean all parts and install new crush washers and the Mustang banjo bolt and torque the bolt to 30-40 lb-ft. Notice that either caliper will mount on either side. You must install the caliper so that the bleed screw is on top pointing up.
7) Install the Caliper onto the Caliper Bracket torque bolts to 23-26 Lb-Ft and install the pad retaining clips into the Mustang caliper and install the pads. The factory pads have a bonded anti-steal material. Any aftermarket pads may need the use of an antisqueal compound or high-temp RTV.
8) Install the rotor onto the hub and temporarily hold in place with a couple lug nuts lightly installed.
9) Work the pads as they are mounted in the caliper assy over the rotor and install the caliper mounting bolts. Torque to 90-95 Lb-Ft.
10) Connect the brake hose to the brake line and remount to the fender skirt.
11) Basically, repeat the previous steps for the other side.
Shown at left is the Mustang setup on my car. On the right is the KVR kit installed.
12) Once complete, you can put the short length of tubing over the bleed screw and open the bleed screw. Pour brake fluid into the master cylinder reservoir so that it stays full enough to prevent air from entering the lines. Watch the hose for fluid flow as gravity pulls the fluid into the caliper and forces out the air. Close the bleed screw when fluid begins to appear. Bleed the brakes as normal. One easy way is to use a handheld vacuum pump setup at the caliper to draw out the fluid which in turn clears air from the system.
DO NOT let the reservoir run dry.
13) Reinstall the wheels and torque the lug-nuts carefully to the proper 90-100 Lb-Ft.
14) New rotors and brake material should be broken in carefully to prevent warpage. Gentle low speed braking should be used to ensure proper stress relief of all materials.
Enjoy.
