Ford Escort rear disc brake conversion

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Escort reardisc.jpg

This article is primarily intended for the Ford Escort, however should also work for the following list of cars:

  • 91-96 Ford Escort GT
  • 91-96 Mercury Tracer LTS
  • 90-94 Mazda Protege
  • 90-94 Mazda 323
  • 92-95 Mazda MX3 GS (V6)
  • 97-02 Ford Escort/ZX2
  • 97-99 Mercury Tracer


The rear disc brake system consists of a solid rear disc brake rotor and a single-piston rear disc brake caliper. The rear brake pads and linings are held in position between the rear disc brake caliper and the rear disc brake rotor by two guides, two shims, and an M-spring. It is not necessary to remove the rear disc brake caliper completely to replace the rear brake pads and linings; the rear brake pads and linings can be removed simply by pivoting the rear disc brake caliper on its rear disc support bracket

Hydraulic power is provided to the rear disc brakes by a rear wheel brake hose attached to the rear disc brake caliper (which can be replaced with Stainless steel brake lines). Replaceable copper washers on either side of the rear wheel brake hose fitting prevent brake fluid leakage.

Rear Disc Brake Assembly

Escort reardiscbrakes01.jpg
  1. Rear Wheel Spindle
  2. Rear Disc Support Bracket
  3. Rear Wheel Disc Brake Shield
  4. Wheel Hub
  5. Rear Disc Brake Rotor
  6. Rear Disc Brake Rotor Screw (2 Req'd)
  7. Rear Axle Wheel Hub Retainer
  8. Hub Grease Cap
  9. Guide
  10. Shim
  11. Brake Pad
  12. M-Spring
  13. Rear Disc Brake Caliper
  14. Brake Caliper Bolt
  15. Copper Washer (2 Req'd)
  16. Banjo Bolt
  17. Rear Wheel Brake Hose


The parking brake rear cable and conduit (2A635) is attached to the rear disc brake caliper at the rear brake operating lever (2N512). When the parking brake is applied, the rear brake operating lever pushes the brake connecting link (2Z999) against the piston, which forces application of the rear brake pads and linings. When the parking brake is released, pressure against the piston is released and the rear brake pads and linings return to their unapplied position.

Parking Brake

Escort reardiscbrakes02.jpg
  1. Parking Brake Rear Cable and Conduit
  2. Rear Drum Brake
  3. Rear Disc Brake
  4. Front Parking Brake Cable and Conduit
  5. Parking Brake Lever


Tool List

  1. Ratchet
  2. Breaker Bar
  3. Sockets - 10mm, 12mm, 14mm, 16mm, 17mm, 21mm (32mm needed for hub retainers).
  4. 10mm and 17mm deep sockets
  5. 1/4" socket
  6. #1 Phillips Head Screwdriver Bit
  7. 10mm flare nut "line" wrench
  8. 8mm box end wrench
  9. 4mm Allen wrench
  10. Needle Nose Pliers
  11. 4lb. Sledge Hammer (or equivalent)
  12. Jack
  13. Jack Stands
  14. Drill or rotary tool with wire brush, or sandblasting cabinet


Obtaining Major Parts

Escort reardiscbrakes03.jpg

Rear disc assemblies that fit the ZX2, 2nd, and 3rd gen Ford Escorts are available from the cars listed in the beginning of this article.

The easiest method for putting rear disc brakes on a ZX2 is to buy the entire crossmember assembly from a ZX2 S/R (or 97-02 Escort with rear disc brakes). The entire assembly can be rebuild, and replaces the existing crossmember. This is usually a more expensive route, and harder to get if it needs to be shipped. The most cost effective way to get rear discs is to remove them yourself, as long as your local junkyard permits it.

The optimum choice for a donor car would have the lowest miles possible, and one that has not been in a junkyard for an extended period of time. Since the major portion of the setup is made of cast iron though, they will hold up to weather and can be restored to good working order. The hub needs to be checked to see if the bearings are good. This is done by spinning the hub on the spindle, and trying to move it from side to side. If it spins fairly well, and there is minimal movement side to side, then they are in good shape. In order to test the hub, the caliper should be removed, as most often the brake pads are stuck to the rotor.


Rear Disc Removal

  1. Since the control arms will be seized to the spindle, it easiest to work on the brakes with the crossmember fully removed from the car. This also helps avoid being beneath the car and also provides better leverage when needed. To do this:
    1. Remove the rear wheels from the car using a lug wrench or a 21mm socket.
    2. Remove the front end of e-brake cables.
    3. Remove the spindle from the struts and trailing arms.
    4. Disconnect the brake lines at the crossmember.
    5. The entire crossmember will drop from the car and can be pulled out from underneath.
  2. Verify that the car is securely supported by jack stands or similar.
  3. Make sure the e-brake is not engaged. Using a deep 10mm socket, loosen the the adjusting nut beside the e-brake handle. This will provide slack on the cable system.
  4. From under the car, locate the cables on each side of the car. The heat shields may have to be removed with a 10mm socket to expose them.
  5. The parking brake cables are attached to the car at both ends, and bolted to the car in 2 places. Remove the clip near the front of the cable, and pull the front of the cable out of the front assembly. It may be necessary to remove the center spring to provide even more slack on the cables to remove them.
    Escort reardiscbrakes04.jpg
  6. Using a 12mm socket, remove the 1 bolt and 1 nut holding the cable to the car. The parking brake cable should only be connected to the caliper. Repeat this procedure for the other cable.
    Escort reardiscbrakes05.jpg
  7. Put a 17mm deep socket on a breaker bar, loosen and remove the bolt that holds the trailing arm to the bottom rear of the spindle. Knock the trailing arm off the spindle with the 4lb. sledge. Repeat on other side.
    Escort reardiscbrakes06.jpg
  8. Using a pair of pliers, slide the brake hose off each strut and position the brake hoses aside.
    Escort reardiscbrakes07.jpg
  9. Put a regular 17mm socket on a ratchet. Place the breaker bar on one of the nuts holding the strut to the spindle, and the ratchet on the bolt side. Break the nut loose, and do the same to the other nut. Repeat this on the other spindle/strut.
    Escort reardiscbrakes08.jpg
  10. Underneath the vehicle, locate the brake line distribution block on the crossmember. Either use a line wrench to remove the lines coming from the front of the car, or cut them with bolt cutters.
    Escort reardiscbrakes09.jpg
  11. Using the breaker bar, 14mm socket and ratchet, remove the 4 bolts (2 on each side) holding the crossmember to the car.
  12. Remove the bolts and nuts holding the spindle to the struts and lower the crossmember to the ground. Carefully slide the assembly out from under the car, so as not to damage the dust shields.
  13. Using the breaker bar, ratchet and 17mm sockets, remove the nuts and bolts holding the control arms to the crossmember. Remove the brake lines from each caliper, using a 12mm socket on the banjo bolts.
    Escort reardiscbrakes10.jpg
  14. You should now have the complete brake assembly, including the control arms. You can attempt to remove the front control arms that are held onto the spindle with a 17mm nut, but the bushings are usually seized to the bolt, and will be easier to take off when you get home.
  15. While you have the crossmember on the ground, now is a good time to remove the 21mm rear sway bar. Remove the sway bar bracket bolts (14mm) and the endlinks. The endlinks are easier to just cut with large bolt cutters.
  16. Now that you have it all loose, take it home.


Disassembly

  1. Now it's time to prepare them to put on the car. The first thing you can do is remove the calipers, e-brake cables, hubs, and dust shields. Once these pieces are off, you can start working on getting the dreaded bolt out of the spindle that holds the control arms. Once you have it all apart, you can clean them all up, rebuild if necessary, and put them on.
  2. The first thing to try to do is loosen the screws holding the rotors to the hubs. Depending on the shape of the screw heads, you might be able to remove them, with a suitable Phillips bit in conjunction with a socket, adapters and a breaker bar. The idea is to try to loosen them now, since the rotors are more than likely stuck to the brake pads. If they can't be loosened without stripping the head, don't worry about them, you can just drill them out later.
    Escort reardiscbrakes11.jpg
  3. The rear calipers are designed to swing open on the spindle, to allow replacement of the brake pads. To do this, remove the 14mm bolt on the rear of the caliper.
    Escort reardiscbrakes12.jpg
  4. Using a 4mm allen wrench, loosen the adjuster screw inside, which will retract the piston back into the caliper. This should loosen the caliper from the brake pads. On the caliper, locate the black plastic dust cap, and remove it.
    Escort reardiscbrakes13.jpg
  5. Using a 10mm socket, loosen the caliper bolt, until it is free from the caliper bracket.
    Escort reardiscbrakes14.jpg
  6. This should allow the caliper to rotate on its hinge.
  7. Once the caliper swung free of the brake pads, remove the "M" springs from the pads using a pair of needle nose pliers, and set them aside for reuse. The pads should slide off of the caliper bracket.
    Escort reardiscbrakes15.jpg
  8. With a 14mm socket, break the bolts holding the caliper bracket to the spindle. Remove the caliper.
  9. If the rear brakes were obtained from an EGT (or that generation), the e-brake cables will be attached to the calipers with a lock nut. Use a pair of wrenches to loosen the lock nut, then pull slightly on the cable to remove it from the bracket. If you have newer rear brakes (from an S/R, etc.), The calipers are attached to the caliper with a clip. Remove the clip and pull the cable away.
  10. Now that the calipers have been removed, the old rusty rotors can come off. If you were successful in removing the screws, give the rotors a few bangs with the sledge hammer to loosen them from the hub. If the screws are not cooperating, drill them down until just past the rotor, and then hit them with the sledge. They should come off once they come loose.
  11. To remove the hub, take a flathead screwdriver and carefully pry the grease cap from the spindle, trying not to bend it up. Unstake the hub retainer by punching the indentation out of the spindle. Then remove the retainer with a 32mm socket and an impact gun. The hub will slide right off the spindle.
    Escort reardiscbrakes16.jpg
  12. To remove the dust shields, take a 14mm socket to the four bolts holding it to the spindle.
    Escort reardiscbrakes17.jpg
  13. You will now be left with the spindle, with nothing left attached but the control arms. Removin the bolt is the most difficult task in the conversion (the second is getting the bolts off your drum spindles). There are four of methods to removing the bolt.
    • Using a propane torch to focus heat only on the spindle while putting an impact gun on the bolt. Slowly the bolt will begin to rotate as the metal around it expands and allows the surfaces bonded by rust to come apart. An impact gun with at least 500 lb of torque is required.
    • Using a press to push the bolt out.
    • Cutting the bolt off flush at the spindle, and drilling the center out, until it comes loose.
    • Taking it to a shop, which may cost around $ 20. Just make sure that they return the spindle, and at least one of the sleeves on either side from the control arms. This will be used as a spacer for the rear control arm. The spacer needs to be approximately 3/4" thick.
  14. Having the complete rear disc assembly taken apart, it is time toclean them up as they're still rusty. This is a good time to check if the calipers are still in a usable condition.

Certain materials in brake pads are hazardous to your health and inhaling them should be avoided when possible. It is best to wear a dust mask or respirator while cleaning them. You can use a wire brush on a drill or similar tool to get most of the rust off of the parts. The ultimate method is to get them sandblasted, as shown. Note the 2 pieces above the 4 long bolts. Those are the pieces used to make the spacers.

Escort reardiscbrakes18.jpg

Caliper Inspection/Rebuild

In order for the brake system to function properly, the calipers must be checked to make sure they are usable. Rebuilding the calipers may not be entirely necessary, but it is relatively inexpensive and not very difficult to rebuild them. Pictured below is an exploded view of the rear brake caliper and its components.

Escort reardiscbrakes19.jpg
  1. Piston Dust Seal
  2. Piston
  3. Piston Seal
  4. Snap Ring
  5. Rear Disc Brake Adjuster Spindle
  6. O-Ring
  7. Brake Connecting Link
  8. Caliper Bolt Dust Boot
  9. Rear Disc Brake Caliper
  10. Brake Caliper Bleeder Screw
  11. Brake Caliper Bleeder Screw Cap
  12. Brake Adjuster Screw
  13. Screw Plug
  14. Rear Brake Operating Lever Seal
  15. Rear Brake Operating Lever
  16. Rear Brake Operating Lever Spring
  17. Caliper Bolt Cover
  18. Caliper Bolt
  19. Caliper Bolt Dust Boot

If the cylinder walls of the caliper are pitted, the caliper cannot be used. It can, however be used as a core to purchase a rebuilt caliper.

A caliper rebuild kit is available at most auto parts stores. NAPA has a kit (part # 2735) that includes the boots and O-rings necessary to completely rebuilt one caliper.

Escort reardiscbrakes20.jpg

Caliper diassembly

  1. Remove the brake caliper bleeder screw and cap.
    Escort reardiscbrakes21.jpg
  2. Remove the caliper bolt dust boots.
    Escort reardiscbrakes22.jpg
  3. Remove the screw plug.
    Escort reardiscbrakes23.jpg
  4. Turn the brake adjuster screw clockwise until the piston is loose enough to remove.
    Escort reardiscbrakes24.jpg
  5. Remove the piston dust seal.
    Escort reardiscbrakes25.jpg
  6. Place a block of wood between the piston and the rear disc brake caliper and remove the piston using compressed air.
    Escort reardiscbrakes26.jpg
    • WARNING: USE ONLY AS MUCH COMPRESSED AIR AS NECESSARY TO REMOVE THE PISTON. EXCESSIVE PRESSURE CAN FORCE THE PISTON OUT OF THE CALIPER BORE WITH ENOUGH FORCE TO CAUSE PERSONAL INJURY. NEVER ATTEMPT TO CATCH THE PISTON BY HAND AS IT COMES OUT OF THE BORE.
    • CAUTION: Do not use a screw driver or any other similar tool to pry the piston out of the bore. Piston damage could result.
    • When removing the piston it is necessary to cover the brake caliper bleeder screw hole and the brake adjuster screw hole.
    • Do not hone the cylinder bore. Pistons are not available for honed cylinder bores. If the rear disc brake caliper bore is scored or corroded, replace the rear disc brake caliper.
  7. Remove the snap ring, rear disc brake adjuster spindle, the O-ring, and the brake connecting link. Discard the O-ring.
    Escort reardiscbrakes27.jpg
  8. Remove the piston seal from the bore, and discard the seal.
    Escort reardiscbrakes28.jpg
    • CAUTION: Use a plastic or wooden pick to remove the piston seal from the rear disc brake caliper bore. A metal tool may scratch or nick the piston seal groove which could result in a leak.
  9. Remove the rear brake operating lever spring.
    Escort reardiscbrakes29.jpg
  10. Remove the rear brake operating lever.
    Escort reardiscbrakes30.jpg
  11. Remove the rear brake operating lever seal.
    Escort reardiscbrakes31.jpg

Installation

Escort reardiscbrakes32.jpg

By now, you should have the major parts cleaned (and painted, if desired), ready to go. To complete the installation, the following parts are required:

  • Rotors
  • Brake Lines
  • Brake Pads
  • Brake Fluid

These parts are readily available in OEM form at most auto parts stores. You may also want upgraded parts. TRINet Motorsports carries performance rotors, pads and stainless lines in a variety of styles and colors (for rotors and lines). Note that the brake lines are the same for the rear discs as they are for the front. Therefore, they carry the same part number. Depending on the condition of the parking brake cables, they may need to be replaced. These can also be ordered from your local auto parts store, or Ford dealership. If you are going to purchase performance brakes for the rear, you can also get matching parts for the front, as shown.

The seemingly obvious first step is to find a nice flat place to raise and support the vehicle. Jack up the entire rear end and support the car with jack stands. Be prepared to have to run somewhere, in case you forgot something, or have the car sit, if you are doing this on the weekend, and the dealer isn't open to get a bolt that got messed up.

Now, the concept with removing the drums is identical to the removal of discs (above).

  1. The parking brake cables are removed the exact same way as above, except the cable on the drum side is connected slightly different.
  2. Remove the trailing arm bolt (17mm).
  3. Unclip the brake line from the strut, and remove the brake line completely (10mm line wrench for both ends).
  4. Remove the struts from the spindle (17mm)
  5. The last part is removing the control arms from the spindle. Again, this bolt can be hard to remove (17mm nut, 21mm bolt head). You may even require buying a replacement afterwards. If so, the part number from Ford is F7CZ-5Z997-AA.

When you have the drum setup off, it's time to put the new brakes on. You are now presented with another choice. You can decide whether you assemble the rear disc setup on, or off the car. Either way will work with the same results.

  1. Mount the spindle on the control arms, with the long bolt and nut. This is where the spacer is used. It goes between each rear control arm and the spindle. Do not tighten the nut just yet.
    Escort reardiscbrakes33.jpg
  2. Loosely attach the trailing arm to the bottom of the spindle.
    Escort reardiscbrakes34.jpg
  3. Loosely attach the spindle to the strut.
    Escort reardiscbrakes08.jpg
  4. Jack the spindle, so that the control arms are parallel to the ground. Tighten all fasteners to spec (17mm Control arms: 64-86 lb/ft, Trailing Arm: 69-94 lb/ft, Struts 76-100 lb/ft).
  5. If you did not assemble the brakes beforehand, install the dust shield to the spindle (14mm 34-44 lb/ft).
    Escort reardiscbrakes17.jpg

Position the hub onto the spindle, install a new hub rear axle wheel hub retainer using an impact wrench (32mm 130-174 lb/ft).

  1. Stake the hub retainer with a chisel or screwdriver. Tap a grease cap onto the hub.
  2. Install the rotors. If you we able to salvage the screws, install them as well (Phillips #1 7-10 lb/ft).
  3. Position the caliper bracket on the spindle and install the 2 bolts (14mm 34-44 lb/ft).
  4. Attach new brake lines to the hard lines on the car (10mm line wrench). Then attach the brake line to the caliper, using a banjo bolt and a copper washer on each side. (OEM 12mm,Techna-Fit 14mm 16-22 lb/ft)
  5. Install the brake pads and M-springs.
    Escort reardiscbrakes15.jpg
  6. Pivot the rear disc brake caliper over the brake pads. Attach the brake caliper bolt (10mm 33-43 lb/ft).
  7. Replace the cap on the caliper bolt.
  8. Using the 4mm allen wrench, "tighten" the adjuster screw behind each caliper until the brake pads just touch the rotor, then turn back the piston 1/3 turn.
  9. Bleed the rear brakes. If you are putting new stainless lines on the front, bleed them as well. Start at the passenger rear, then driver rear, the passenger front, and finally the driver front. Make sure that the brake reservoir is full of fluid while bleeding the brakes.
  10. Adjust the parking brake lever, using a 10mm deep well socket.


Break-in Procedure

If all went well, you should have a nice set of brakes on your car. But before you go try stopping hard from 75 MPH, you need to do one last thing - break in those new rotors and pads. Drive around a residential or business area where you can drive up to 25-30 MPH. Take your vehicle up to about 25 MPH, and brake to about 10 MPH. Repeat this step 15-20 times. After doing that, you can do regular driving but still take it easy on the rotors for another 10-20 miles. Apply the brakes gradually instead of slamming on them.

Also see

  • Ford Escort & ZX2 section for the entire index of all Ford Escort and ZX2 related articles.