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SVT Rear Brake upgrade

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Location
Michigan
#1
After cleaning off and installing a junkyard set of Focus SVT Caliper Brackets and installing new rotors and pads, I've been trying to figure out where exactly juttering in the steering wheel was coming from during brake application. It seems that it is not my unbalanced wheels but from the new brakes. A week after I bedded them I felt the jutter and assumed it needed another heat cycle so I did the bedding proccess again to no avail. Every once in a while I did some high speed stops on the highway but nothing helped. Recently I went to take a look at the brakes and saw extreme uneven padwear and a crazy amount of wear from trying to get them to bed evenly. Here are a couple pics, I'm ordering some new pads and I'm going to take them apart asap to try and find an issue.

Do you guys have any Ideas of what could be causing this?
20200319_122321.jpg 20200319_122346.jpg
 


OP
zeddzik
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Michigan
Thread Starter #4
What kind of pads you Running?

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I went with Motorcraft BRF1444 from Rock Auto but I might go with Ferodo DS2500s to match the fronts.

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OP
zeddzik
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Michigan
Thread Starter #5
Ideas — Make sure the pins are lubed and moving freely... and don’t run an overly aggressive pad.
I'm definitely going to check that as well and re-lube the pins, the brackets were heavily corroded and it is quite rough inside the sockets. Also could you explain why you think it could be because of an overly aggressive pad?

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Messages
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Location
Phoenix, AZ, USA
#6
Also could you explain why you think it could be because of an overly aggressive pad?
More aggressive pads can develop a shudder if brake parts and brackets have some flex, and with the whimpy floating caliper and longer bracket, I can see this being a possible cause.
 


OP
zeddzik
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Michigan
Thread Starter #8
Make certain the nubs that stick out of the back of the pads are seated within the gap of the X of the piston.
Yep that was the issue.
The one on the right is what it's supposed to look like and the one on the left was causing the problem.


And here's some more pics of the problem one.



Oh and I was double-checking the torque on my lugs after a tech broke a stud a couple weeks ago and on the other side they totally fucked up and crossthreaded another one....



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olson7874

New Member
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Mokena
#9
Can the rear calipers off the SVT be used along with the brackets, or are the brackets the only part that fits? I'd like to replace the whole thing if it works.
 


OP
zeddzik
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Michigan
Thread Starter #10
Can the rear calipers off the SVT be used along with the brackets, or are the brackets the only part that fits? I'd like to replace the whole thing if it works.
Yep the calipers will fit, but I'm not sure if the line fittings and parking brake hardware is the same.

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OP
zeddzik
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Thread Starter #12
NVM then haha Oh and still getting the shuddering so I think it might be a wheel balance issue or something else entirely.

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TyphoonFiST

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#13
NVM then haha Oh and still getting the shuddering so I think it might be a wheel balance issue or something else entirely.

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When? Braking or accelerating?

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OP
zeddzik
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Thread Starter #15
Its the worst when braking at high speeds but goes away as brake pressure increases. Passenger side wheels weren't dynamically balanced so that could be the issue as I wasn't able to fit weights close to the spokes with the limited clearance in the front.

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TyphoonFiST

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#16
Or a rotor is now out of Round*



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Last edited:
OP
zeddzik
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Thread Starter #17
Or a rotor is now out of Round*


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Could be the case, could that happen within the a few weeks of a new install? I doubt it's the front 315x28mm rotors, they are massive so I doubt I got them hot enough to warp them and they are floating so I would think that would minimize the vibration.

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TyphoonFiST

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#19
You would have to use a dial caliper and check the Runout to see if they are out of round. Warping rotors seldomly happens...they become out of round. Warping usually happens when they get cooked ...liked a 1000° plus of repeated heavy braking.

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CarGuy

Active member
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#20
You would have to use a dial caliper and check the Runout to see if they are out of round. Warping rotors seldomly happens...they become out of round. Warping usually happens when they get cooked ...liked a 1000° plus of repeated heavy braking.

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Especially rear brakes.

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