GT Rotor Brake Installation
by Bob Cosby

Third Generation Mustangs are not known for their spectacular brakes, mainly because they don't have em. It is a well-known joke on the drag strip that the last turn-off is reserved for "Mustangs Only." This was largerly corrected in 1994 with the introduction of 4-wheel disc brakes on the SN95's. But what are those of us with older car supposed to do? Most of us modify our cars to go faster. We pour a great amount of money into going faster. Often we neglect to give enough attention to the fact that we must also come to a safe stop. As speed increases, the demands on the braking system increase to.

The Mustang Enthusiest has several brake choices. He or she could simply replace the pads and shoes, turn the rotors and drums, and probably be ok in most situations. If more stopping power is desired, there are several 4-wheel disc conversion kits available. While this will give you an incredible increase in braking ability, it will probably also give an an incredible decrease in the amount of available cash you have once finished. Is there a happy medium?

There sure is. A company called GT Rotors has just the thing for folks with tired brakes that want to upgrade, but without having to upgrade their paycheck. GT Rotors sells a stock replacement kit that comes complete with new front rotors and pads, along with new rear drums. And these aren't your ordinary brakes...

The Rotor kit I installed on the front of my LX was part number 75-0234. It included two new rotors with matching pursuit quality pads. The rotors are dotted with "dimples" that allow gases generated by the pads and rotors to dissipate quickly, thus increasing the efficiency of the brakes. The pads are designed to stand up to greatly increased braking effort and still continue to provide excellent stopping power, far beyond what the stock pads can provided.

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The Drum Kit, part number 22-8890, included two new drums with matching shoes. Taking a look inside the drums shows twin groves crossing along the inside of the drums. These grooves serve the same purpose as the dimples on the rotors.

As mentioned above, this set is a direct replacement for the stock rotors, drums, pads, and shoes. Installation is the same as it would be for stock pieces. Anybody with very basic mechanical skills could easily accomplish the install. I used a Haynes manual for an added reference.

The tools I used were:

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4-way Wrench
Large, medium, and small flat-head screwdriver
Needle-nose pliers
Regular Pliers
Torque wrench
1/2" drive rachet
5/8" socket
3/4" socket
Mallet
Hammer
New Cotter pins
Quality wheel bearing grease

I started with the drum brakes on the back.

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I do back brakes one at a time, using the other side as a reference in case you forget just how something goes. Put the car on jackstands and remove the wheels, then remove the drums. Make sure the emergency brake is released or the drums will not come off. Sometimes a light tap on the drum with a hammer is required.

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This exposes the brake shoes, springs, and associated hardware.

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Using a pair pliers, I removed both of the top springs and placed them in their correct place on the new shoes (purchased extra) that I had set on the ground below the old ones.

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Then I took off the self-adjuster and its parts, and finally removed the shoes by taking off the restraining springs on each. Re-assembly is basically the opposite of removal. I set the shoes in first with the retaining spring. Then I put in the self-adjuster and its related components, except the spring that pulls the bottom of the shoes tight. Next I installed the two upper springs. The last main step, after making sure that all springs and the adjusting wire were in the correct place, is to pull the bottom spring into place. That is the single hardest part of the entire install. Finally, put the drum over the shoes.

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The drum should fit very easily and be very loose. Take the drum off and turn the self-adjuster out a few turns, then put the drum back on and see how tight it is. Repeat this until the drum is hard to get on, then back the self-adjuster
off a notch or two until the drum just slides over the shoes with no interference.

Replace the rear tires, take the car off the jackstands, and test the rear brakes. I do this by using the parking brake. It should hold the car when you try and go forward or back with a moderate amount of power. You should also take a short drive and listen for any unusual noises.

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For the front, raise the vehicle on jackstands and remove the tires. There are several ways to install front pads. Here's the way I do it; loosen the bolts that hold the calipers on. Gently tap the caliper up, as if you are taking it off the rotor, but only go enough so that you can get a large screwdriver lodged on the inside pad so as to compress the plunger back into the caliper housing. If you are changing rotors (as I was), you don't really need to worry about the rotor. However, if you intend to have the rotor turned and then re-use it, be very careful that you don't scar the rotor surface.

Once the plunger is all the way back into the caliper, remove the caliper, >remove the pads, and set the caliper aside, but DO NOT let it hang from the brake line!. Next, pop the grease cap off with a small screwdriver and a hammer. Pull the cotter pin out of the nut and remove the nut (make sure you have a new cotter pin for the reassembly). Grab the rotor and gently pull it off the spindle. This might require a little bit of jerking to get it loose.

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Depending upon the mileage of the car and the condition of the bearings, you can either replace the bearings and seals, or re-use them. If you use the old bearings, make sure you clean them thoroughly to remove all the old grease, then repack them with quality new grease.

The install of the new brakes is the reverse of the removal.

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For my installation, everything went smoothly and I'm very happy with the results. Gone is the high-speed braking vibration my stock brakes had, and the low speed pulsing. Brake feel is GREATLY improved, with a much broader range of play than I had before.


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