• Sign Up! To view all forums and unlock additional cool features

    Welcome to the #1 Fiesta ST Forum and Fiesta ST community dedicated to Fiesta ST owners and enthusiasts. Register for an account, it's free and it's easy, so don't hesitate to join the Fiesta ST Forum today!


Pads not grabbing rotors all the way

Messages
22
Likes
2
Location
Morgantown
#1
So, my rear pads are not grabbing the rotors evenly. Both sides.

I pulled the calipers and the pistons are extending all the way when I touch the pedal, and both guide pins are greased to heck and move easily.
Brakes were bled, and re-bedded after I greased everything up. The pads are fine and the rotors look ok as well and not warped to the eye.
Thoughts on why this might be happening? Could the pad/rotors be slightly warped?
 


OP
G
Messages
22
Likes
2
Location
Morgantown
Thread Starter #2
Also - when I try to upload a picture to my albums it says that I am out of space. I only have 5 pictures total in 2 albums, so can any admins give me any more space? The picture I am trying to upload is all of 132 kb.
 


Messages
182
Likes
54
Location
Gatineau
#3
Do you mean that the exterior pads are not grabbing as much as the interior pads? Or you mean that the front of the pads are used more than the rear of the pads?

The first one is normal, every one of my cars always had the interior pads more used than the exterior pads.

For the second, it's certainly not normal and the only thing I could see is broken calipers, but you said that you took them out, so that's a no go I guess.
 


OP
G
Messages
22
Likes
2
Location
Morgantown
Thread Starter #4
I should have clarified my statement. So the interior pads are grabbing fully. The exterior pad is grabbing more towards the outside of the rotor, and not on the inside towards the hub. At rest with the parking brake off, you can just barely see that the pad LOOKS to be sitting to where the part toward the hub is contacting and the part towards the outside is not. But looking at the rotor marks it turns out to be the opposite.

In the past when I've seen something like this the pad was actually locked up a little and not moving - it was actually pivoting a little. I would think this could be happening here but I also took the thing off and greased the heck out of it, so that shouldn't be the problem.
 


Intuit

3000 Post Club
Messages
3,573
Likes
2,168
Location
South West Ohio
#5
Use OneDrive or GoogleDrive to post a photo.

https://onedrive.live.com/
https://drive.google.com/

There's a minimum thickness spec for the rotor. What year is the vehicle and how many miles?

If the pad is not seated properly against the rotor then either the wrong pad is installed or it has come apart.

With a prior vehicle, the parts store was handing me pads for a car with the 13" wheels as opposed to my car with the 14" wheels. Different rotors and calipers were used with the larger wheel. This left a large inner ring on the rotor, unused.
 


kivnul

1000 Post Club
U.S. Army Veteran
Messages
1,193
Likes
710
Location
Deer Park, WA
#6
I've been meaning to post about this. The rear pistons have a X shape contact surface. The pads have a nub about the size of a pencil eraser. This nub MUST sit within the crevice of the X. If it is not, the whole pressure of the piston will push on the nub, causing uneven wear. My sons fiesta had one of its rears this way. When I redid my brakes I didn't know about this. When I took them back apart I also messed up on one of them. This may be what is ailing you.
 


Messages
206
Likes
39
Location
Indianapolis
#7
I've been meaning to post about this. The rear pistons have a X shape contact surface. The pads have a nub about the size of a pencil eraser. This nub MUST sit within the crevice of the X. If it is not, the whole pressure of the piston will push on the nub, causing uneven wear. My sons fiesta had one of its rears this way. When I redid my brakes I didn't know about this. When I took them back apart I also messed up on one of them. This may be what is ailing you.
Additionally, the rear piston can be adjusted in and out by rotating the exposed piston. Use a brake caliper adjustment tool. (a set of channel locks can be used, but be careful to not damage the seal or dust shield)
 


Messages
528
Likes
123
Location
JeffCo
#8
Also - when I try to upload a picture to my albums it says that I am out of space. I only have 5 pictures total in 2 albums, so can any admins give me any more space? The picture I am trying to upload is all of 132 kb.
You can attach the picture directly to the thread, that way it doesn't take up space in the album. Or share it from a hosting site.
 


TyphoonFiST

9000 Post Club
Premium Account
Messages
11,476
Likes
7,967
Location
Rich-fizzield
#9
Caliper pins seized? Brake pad hardware worn? Is there pad slap happening?

Sent from my SM-N950U1 using Tapatalk
 


OP
G
Messages
22
Likes
2
Location
Morgantown
Thread Starter #10
So I don't know why this picture makes the rotor look so bad, but you can see the outside part of the pad is grabbing and about half way down it stops. I have pulled the rotors and calipers and as of now the pins are greased and move free, as well as the pads themselves. I have held the pads up to the rotors and at least to the eye they make contact top to bottom. They aren't the stock pads so they don't have the nipples on the back to fit in the X of the piston. I can leave the piston free and barely touch the pedal and it extends freely, and also contracts back in when I screw it in freely. I seriously think at this point they are just worn out from being cheap crappy pads that the Ford dealer put on when I bought the car last year. Car still stops great so I am probably just going to drive it for a while then do all new rotors/pads all the way around sometime next winter.
https://drive.google.com/file/d/1QhI_HVNQ4i5mJMz7Lr1YfsHPJ4uech7_/view?usp=sharing
 




Top