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GT500 Pedal Assembly Install

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I installed the GT500 Pedal assembly yesterday. It was pretty simple and straight forward. I used the Ford Workshop Manual directions as a guide.

1. I started by having a nice ice cold miller lite to loosen me up for the tight quarters I would be working in. This step is optional :)

2. I rolled my windows all the way down before I disconnected the battery. I do this because the window will not "dip" when you open the door or close it making it hard to get the door open and closed. I then disconnected the battery using an 8MM socket and ratchet.


3. I then removed the seat. You will need a 15MM deep socket for the rear nuts and a 13MM socket for the front. To access the rear nuts you have to remove the plastic trim pieces first by pulling straight back on them. After all the bolts and nuts are removed slid the seat forward and the seat back fully forward as well to ease removal. Also dont forget to unplug the two harness underneath the seat.



4. I then prepped the area under the hood to catch the brake fluid that will come out when you disconnect the lines. Use a pick or small flat head screw driver to pull the retaining clip back so you can remove the line from the master cylinder to the transmission. Be careful it will be easy to lose. Once out pull the line out and then push the clip back in. For the line from the reservoir to the master cylinder use needle nose pliers and pull the clamp back about an inch then pull the hose off the reservoir side. Refer to the shop manual link for a detailed picture of these pieces. I cut a water bottle in half and placed it to catch any drips that would come out of the reservoir.



5. Now moving to under the dash to the meat of the removal. First there are three switches that you must remove from the assembly one on the brake pedal and two on the clutch. these are an easy quarter turn to remove.




6. Next remove the Brake booster push rod clevis locking pin. Follow the shop manual to remove this. I used an 11MM wrench to slip over the two tabs then a flat blade screw driver to pry it out. Manual says this is a one time use item....I reused it didnt see anything wrong with it. Cant really get a camera up in there to take a pic so I took one of it out.


7. There are a total of 4 nuts and 2 bolts to remove to get the pedal assembly out. All of them are 13MM you will need a deep socket for the nuts. Refer to the shop manual for location. Once they are out you will have to maneuver it a little to get it out.

Now that it is out I did a side by side and the only difference that I could note between the two were the addition of the assist spring and a lighter return spring for the brake pedal. I went as far as taking the assist spring off and push both the clutch pedals with my hand and its the same amount of tension. Looked to me that they just added a pin to the pedal and put that spring in place. So to save yourself time and money just remove the spring and you have a GT500 pedal assembly........yeah now you know.



Boss brake pedal return spring

GT500 brake pedal return spring

But I went ahead and install it anyway.

Install is reverse of removal. One thing that would have been helpful was having someone hold the brake booster in place as it is now loose from removing the four nuts. After it is installed and the seats are back in place bleed the system and you are done.

For me I first put it under vacuum for about 20 mins till it no longer lost pressure. Then pumped the pedal about 200 times. topped off the fluid. I use duct tape and one of my wifes hair tie things to get a good seal and poke a hole in the tape. This gets me a great seal. I then performed idle relearn and took it for a test drive.


On the test drive the pedal is much firmer and smoother without having that dreaded transition point that makes engaging the clutch smoothly difficult with a twin disc clutch.

In the end just remove the assist spring there is no need to buy the entire assembly as all the parts and pieces are the same. I checked all the part numbers on them and they all matched.


Save the dawn for your dishes!!!
Justin, thanks for posting this but sorry it's not different. I read elsewhere that the bracing was different on the GT500 frame but from your observations it's not. Does the GT500 have any helper spring or is it completely omitted?
no helper spring at all. the GT500 arm is the same as the boss has the hole there to set the pin in and weld it in for the assist spring. the top perch is already there on the plastic side of the housing.


Save the dawn for your dishes!!!
Brandon302 said:
What made you decide to go through all that trouble instead of removing the assist spring and calling it a day.
cause I bought it almost a year ago before I knew that it was the same thing as removing the spring. I have a spare now.

I took it for a drive today and its taking some getting used to but it is better. I have to relearn letting it out from a stop.

Grant 302

basic and well known psychic
Awesome write-up. Glad I don't have to do it!

This is my solution for adapting the mityvac to the reservoir:


It's a rubber washer under a fender washer to the suction cup attachment.


Save the dawn for your dishes!!!
YellowJacketBoss302 said:
Hi Justin. Thanks for the write-up. Is the clutch engagement/disengagement point the same with the two pedals?
feels like it. hard to tell without that binding spot and the assit spring gives you about a few mm of false resistance. where the GT500 is a loose pedal when all the way out. hard to describe. Those of you that have taken the spring out might know what I am talking about.
Nice, you finally put it in. Seems like you're getting the hang of doing a proper write-up too man lol. 8) GJ, sucks that it's the same shiznit tho


Save the dawn for your dishes!!!
jneary said:
what is the red handled thingy in the GT500 part?
its a temp thing to keep the clutch pedal from moving. not sure why they have it on there but I am guessing to keep from sucking in unwanted debris into the master cylinder while installing it.

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