Brakes 96-04 5 lug brake swap

Now i know this is already been done been hashed out but that should only help to keep this thread related to swapping 96-04 brakes onto a fox… that being said i have a 94 gt booster and master cylinder with 04 front calipers 94 rear end, i have the rock auto specials stop tech ceramic pads no fancy rotors, i have a willwood proportioning valve ive been messing around with, so i know this is not going to feel like stock new edge brakes but i know i shouldnt have about an 1.5 inches of mush before real pedal engagement… i bled the system out good. What are the thoughts here different booster? Different master cylinder? Thats just how it is ?
 
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Pedal should be firm from the start. Is the MC from the ‘94 or is it new/reman? Did you bench bleed it? When you bled the system did you do it by hand or with a pressure bleeder? Are all of the bleeders on the calipers at the high point when installed? Did you gut the proportioning valve out of the combination valve? Did you check the gap between the brake booster rod and the MC?
 
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Now i know this is already been done been hashed out but that should only help to keep this thread related to swapping 96-04 brakes onto a fox… that being said i have a 94 gt booster and master cylinder with 04 front calipers 94 rear end, i have the rock auto specials stop tech ceramic pads no fancy rotors, i have a willwood proportioning valve ive been messing around with, so i know this is not going to feel like stock new edge brakes but i know i shouldnt have about an 1.5 inches of mush before real pedal engagement… i bled the system out good. What are the thoughts here different booster? Different master cylinder? Thats just how it is ?

I would suspect you might still have air in the system.

WIth the 99-04 GT calipers/SN95 rears you should be running the 1993 Cobra 1" bore MC. That's how ford equipped the 99-04 V6 cars as they used vacuum brakes in 99-04 with a similar booster to the 94-95 mustang. Pedal ratio is a tad different, so some folks do find the 1" to be a bit on the softer side.

WIth the 94-95 GT 1 1/16" MC, if you get all the air out of the system, that pedal should be pretty firm. Now, you might like it, you might not, but based on your post I suspect you still have a lot of air to get out.


Did you bench bleed the master cylunder before installing it and then proceeding to bleed the rest of the brakes? If not, you'll never get the air out. Also, with the engine off, that pedal should be hard as a rock with no real movement. If it's still spongy with the engine off, you definitely have air.

I would recommend working on removing the air and trying out the pedal feel first. If you find it too firm and requiring too much pressure to stop the car, then you can step down to the 1" 93 cobra MC
 
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Thank you thank you thank you this is what i was hoping to achieve with this thread! The 94 booster and master cylinder was installed like 3.5 years ago and has been on the car since then( before 96-04 i had sn single piston ) i didnt know of booster adjustment at the time so i never did that just pulled from the donor put on the fox, i did gut the stock proportioning valve and got the plug, ill start with trying to bleed again, bleeders are all install correctly. Now when you say hard as a rock with the engine off you mean like after a pump or two or like engine off and pedal is rock ? Thanks again folks big help
 
No, if the brake system is 100% the brake pedal will be solid when you jump in the car with the engine off. If you are having to pump the pedal a couple of times then you have air in the system.

If you pulled the booster and MC out of the same car chances are the booster rod is adjusted correctly. This is an example of the tool to check the gap between the booster rod and the MC piston:


I would start over and bench bleed the MC but that is me. Its more work but at least you will know it is right. You very well could have a bad MC in that it is bypassing fluid around the piston which would require a new MC.
 
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No, if the brake system is 100% the brake pedal will be solid when you jump in the car with the engine off. If you are having to pump the pedal a couple of times then you have air in the system.

If you pulled the booster and MC out of the same car chances are the booster rod is adjusted correctly. This is an example of the tool to check the gap between the booster rod and the MC piston:


I would start over and bench bleed the MC but that is me. Its more work but at least you will know it is right. You very well could have a bad MC in that it is bypassing fluid around the piston which would require a new MC.
Oh i see yeah banking on air still being in my line forsure, prior to swapping the 96+ dual pistons up front pedal feel was good( was driving with the old setup a month or so ago) brake fade was the main reason for upgrade, i will try bleeding the system again probably do it a few times… if my pedal still doesnt feel right ill try bench bleeding the mc watched a quick video not bad at all to get that done just dont wanna if i dont have too lol
 
vacuum booster may have residual pressure in it from last time the engine ran, depending on how long ago that was.

Really you just need ot give it a couple presses to vent that vacuum, but if you are pressing it and it's still soft, then you have air in the system or the booster rod is adjusted too sloppy.
 
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If you installed the master cylinder/booster as a unit when doing the swap then bled the brakes there most likely is air in the master cylinder, start there by pulling the master cylinder and bench bleed it, some have had success jacking up the rear enough to level out the mc and bled it but the mc has to be level or you will not get the air out.
you may be wasting time and money (brake fluid) if you don't check the mc first.
 
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The m
If you installed the master cylinder/booster as a unit when doing the swap then bled the brakes there most likely is air in the master cylinder, start there by pulling the master cylinder and bench bleed it, some have had success jacking up the rear enough to level out the mc and bled it but the mc has to be level or you will not get the air out.
you may be wasting time and money (brake fluid) if you don't check the mc first.
The mc and booster was done as a unit but about 3 years ago and i didnt bench bleed it then so ill dig into all this
 
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Same here. I install the MC into the car with the bench bleeder kit still on it then pull the bench bleeders off one at a time and quickly get the metal lines installed into the MC. I just figured it was one less step and honestly it just seemed easier. Be sure to put something to catch the brake fluid as that crap is corrosive.
 
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Same here. I install the MC into the car with the bench bleeder kit still on it then pull the bench bleeders off one at a time and quickly get the metal lines installed into the MC. I just figured it was one less step and honestly it just seemed easier. Be sure to put something to catch the brake fluid as that crap is corrosive.
My understanding is that when you do it this way you do not push the MC piston all the way forward to bleed out all of the air...
 
My understanding is that when you do it this way you do not push the MC piston all the way forward to bleed out all of the air...


I think he means he bleeds it off the car with the screwdriver, but then just installs the MC into the car with the bleeder lines still hooked up, and then does a swap.

That's how i do mine. Bleed off car. Install. fast changeover and tighten, and then bleed the calipers
 
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Correct, bench bleed out of car, leave plastic fittings and lines on the MC, install into car, remove one plastic fitting and line and quickly attach associated hard line then do the other, and finish up with pressure bleeding the brakes.
 
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The easiest and best thing I ever did was to get metal fittings and flared short pieces of brake line that fit the master cylinder. I used pet store air pump clear hose to run from the short ( 1 inch long ) brake line ends that stick out of the fitting and ran them up into the reservoir. You can then put it in a vise and use a screw driver or install it and slowly pump the brakes. The ends of the plastic tubes must stay submerged in the reservoir. The plastic fittings seem to always leak or strip our. You could take some off a mustang in the JY. You just need short ends where the go in the master cylinder.
 
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The easiest and best thing I ever did was to get metal fittings and flared short pieces of brake line that fit the master cylinder. I used pet store air pump clear hose to run from the short ( 1 inch long ) brake line ends that stick out of the fitting and ran them up into the reservoir. You can then put it in a vise and use a screw driver or install it and slowly pump the brakes. The ends of the plastic tubes must stay submerged in the reservoir. The plastic fittings seem to always leak or strip our. You could take some off a mustang in the JY. You just need short ends where the go in the master cylinder
 
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Thank you guys for all the good information! I got lucky bleed the brakes out definitely had some air pockets pedal is way more touchy i really like the new brakes! Now it seems my brand new power steering pump is no good theres a metallic sound the second i turn the car on, it’s definitely 110% power steering pump but im just confused its brand new all new fluid? I looked to see if the pulley was making contact anywhere somehow its not sounds like bad bearings if i can ill post a short video
 
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