Brake caliper locked

Black GT

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The right front brake caliper is locked on my 2001 GT. It had been lightly hanging up for awhile but the other day I went to move the car and all it would do is spin the rear tires. Finally it letup enough for me to move the car but was still heavily dragging. What causes this to happen and can I rebuild the caliper or should I scrap it and get a new one? New they are about $80. or I can get a used one for $11.99. Not sure if used would be that great an idea though.
 
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weendoggy

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The right front brake caliper is locked on my 2001 GT. It had been lightly hanging up for awhile but the other day I went to move the car and all it would do is spin the rear tires. Finally it letup enough for me to move the car but was still heavily dragging. What causes this to happen and can I rebuild the caliper or should I scrap it and get a new one? New they are about $80. or I can get a used one for $11.99. Not sure if used would be that great an idea though.
One thing, most important, that is always overlooked are the brake hoses. They will look good on the outside, but bad inside. They can and have restricted fluid to give a locking caliper/brake sensation. However, this is not always correct but should be addressed especially if the car is of age and/or many miles. With that said, I'd replace everything, i.e. calipers and hoses. Add pads/rotors if needed. Rebuilt calipers are better than "used" ones. You can put stock brake hoses back on or opt for some good SS ones. Be sure to bleed the entire system when done. Many times, a lot, people don't change their brake fluid. This should be done every few years as it attracts moisture.

So I take it your left front caliper spins? If so, I'd still do both. jmo
 
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Black GT

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Thanks for the reply. I never thought the brake hose could be the cause. I will take your suggestion and replace the calipers and hoses. The car has felt like a brake was dragging for over a year (not a daily driver but a fun one). It was easy to tell which one was dragging by feeling the temperature of the wheels. The dragging one was very hot.
 
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7991LXnSHO

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Ashley is very pleasant to gaze upon. Good choice.
Now what were we talking about?
 
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weendoggy

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Thanks for the reply. I never thought the brake hose could be the cause. I will take your suggestion and replace the calipers and hoses. The car has felt like a brake was dragging for over a year (not a daily driver but a fun one). It was easy to tell which one was dragging by feeling the temperature of the wheels. The dragging one was very hot.
The problem is, brake fluid is applied with high pressure (via your foot, brake pedal and master cylinder). When you release the pedal, pressure is returned to the master cylinder by the caliper pistons being relieved of pressure and rotating rotor to allow them to return at ease to seat. This means the de-pressurized fluid can return to the MC. Now, if there's a blockage (due to inner hose deterioration) the fluid remains under a certain amount of pressure, depending on how bad the restriction is. So, the fluid can't return and the brake drags. Taking that lesson, it doesn't mean it's always the hose, but it can be, especially on high mileage or heavy use vehicles.
 

Mustang5L5

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This is very common with the 99-04 GT PBR calipers. The phenolic Pistons have a habit of sticking in the piston bores..badly,

you don’t be able to rebuild the caliper as it will require a little machining to clean up the bore and possibly a new piston. You are better off buying a reman caliper and just swapping it.

don’t buy a used caliper, as it may be bad from the onset.

To reduce the chance of these caliper sizing, you’ll want to stay on top of brake fluid changes. This issue seems to rear its head when the car tends to sit for prolonged periods
 
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Black GT

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Are there different sizes brake line bolt sizes for these cars? A friend of mine had a crashed New Edge mustang that had recently had new calipers, rotors and pads. She said I could have the right front caliper as her car was totaled. The caliper looks identical to mine. Today when I went to swap them out I could not get the brake line bolt to start in the new caliper. They look the same size but it will not thread into the hole. I ended up threading it back into the old stuck caliper just to keep my brake fluid reservoir from leaking all the fluid out. It then started thunder storming so had to leave it that way until tomorrow. The caliper came off a 6 cylinder mustang and my car is a GT. Do they have different calipers?
 

Mustang5L5

Put lubricant all over the balls
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Yes. Ford used a mix of fine thread and coarse thread calipers for the 99-04 GT/V6 PBR.

I believe it was broken down as 99-00 got one type, and 01-04 got the other. I don’t recall which was which.

just take a banjo bolt from the other car. Calipers are exactly the same otherwise
 

Black GT

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Yes. Ford used a mix of fine thread and coarse thread calipers for the 99-04 GT/V6 PBR.

I believe it was broken down as 99-00 got one type, and 01-04 got the other. I don’t recall which was which.

just take a banjo bolt from the other car. Calipers are exactly the same otherwise
Thanks, That is my problem. Evidently 99-00 has the coarse threads and 01-04 has fine threads. I looked in the new caliper hole and looks coarse. Also I noticed when I took the caliper off the parts car the brake line bolt had a 12mm head and my car has a 15mm bolt head.
 

Mustang5L5

Put lubricant all over the balls
Mod Dude
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Test the pistons on that caliper prior to install. Those PBR calipers tend to seize when the car has been sitting a while. That's why used/junkyard calipers may not be the best option sometimes.
 
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weendoggy

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Also I noticed when I took the caliper off the parts car the brake line bolt had a 12mm head and my car has a 15mm bolt head.
Don't worry about the hex head size of the banjo bolt. New bolts will most likely be 10mm, 11mm or 12mm. That 15mm is a big block type that was used. Once you find the correct thread pitch you can purchase new banjo bolts. fyi, my front hex takes a 10mm while the rear is a 11mm
 
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Black GT

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Dang, I had to pry the old caliper off. It had a grip on the rotor. The pistons are locked tight. Should the strut be at that angle where the spindle attaches? The previous owner lowered the front. I like the rake but its a rough ride. IMG_0293.jpg IMG_0291.jpg
 

weendoggy

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Dang, I had to pry the old caliper off. It had a grip on the rotor. The pistons are locked tight. Should the strut be at that angle where the spindle attaches? The previous owner lowered the front. I like the rake but its a rough ride.
Yes, that looks normal. Previous owner most likely just put lowering springs in to do the job. That's what sets the ride height. You can look at shocks to see what/if anything was done there. Sometimes you can combat the stiff ride with adjustable shocks to give a better rebound. If they're too stiff, it'll rattle your teeth.

If you had to pry to caliper off, I'd ditch those for rebuilt ones unless the others you have are good. I know everyone tries to save $$ but dealing with safety items is not a good way to shortcut things.
 
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weendoggy

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Too bad they didn't install adjustable shocks. There's so much you can do suspension wise to increase the handling and ride, it just takes $$ and time. Much of it can be done by yourself if you're somewhat mechanically inclined to save lots of $$.

If you were looking for better brakes I'd invest in stock Bullitt, Mach I or Cobra brakes. Direct change and you need 17" wheels.
 
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Black GT

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I will look in to that. Already have the 17" wheels. What is a good brand of adjustable shocks? Would love to make the ride smoother. As it is right now a little bump is a big blam. IMG_0511.JPG IMG_0517.JPG