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Soft Brake Pedal - New MC?

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Old Jul 2, 2020 | 08:45 AM
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Default Soft Brake Pedal - New MC?

I have a soft pedal (too much travel). If I pump them up, they do get hard (giggity) and don't seem to fall when holding it. I did a full bleed a couple of months ago and the problem still seems to exist (although the car stops just fine). I used a vacuum bleeder, so potentially I could have just done a bad job. But I also just noticed that my right rear rotor is getting torn up. I replaced both rear ones last year since they were both dug up pretty bad (they were the stock ones). The left rear is fine as with both fronts. My pads were in pretty good shape (probably around 50%+). Could it just be a bad bleed, or I did it wrong or do you think I need a new MC? (I have done a bunch of reading on it, and I followed things correctly, so I don’t think I had the procedure wrong). Any thoughts would be appreciated. Thanks. Paul. (as an FYI, it’s and 08 is250 awd with 64k on it).
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Old Jul 2, 2020 | 10:15 AM
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Originally Posted by Pablorock
I have a soft pedal (too much travel). If I pump them up, they do get hard (giggity) and don't seem to fall when holding it. I did a full bleed a couple of months ago and the problem still seems to exist (although the car stops just fine). I used a vacuum bleeder, so potentially I could have just done a bad job. But I also just noticed that my right rear rotor is getting torn up. I replaced both rear ones last year since they were both dug up pretty bad (they were the stock ones). The left rear is fine as with both fronts. My pads were in pretty good shape (probably around 50%+). Could it just be a bad bleed, or I did it wrong or do you think I need a new MC? (I have done a bunch of reading on it, and I followed things correctly, so I don’t think I had the procedure wrong). Any thoughts would be appreciated. Thanks. Paul. (as an FYI, it’s and 08 is250 awd with 64k on it).
Well, vacuum bleeding is good for filling new lines but generally speaking, is not effective and leaves the pedal mushy as you describe.

Get a friend and pressure bleed them. Start in the rear;
Push and hold pedal pressure, open bleeder w hose on it, close bleeder when pedal bottoms, release pedal.
Repeat at least 6x per caliper and don't let the MC run dry.

Now if you want to take that a step further and really improve it, repeat the above procedure but before cracking the bleeder, tap updward on the caliper body with a piece of hardwood to dislodge trapped air bubbles. Unlike vacuum pulling and dispersing trapped air, pressure will condense the air so multiple small bubbles form a larger one having enough mass to rise to the bleeder from the tap tap tap action.

When done, the pedal should be instant on.

Also, if after a short drive one rotor is hot, the rear floating caliper may have seized. This is a common problem and I'd suggest replacing the caliper before bleeding if it is suspect.
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Old Jul 2, 2020 | 02:51 PM
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Thanks for the info. I was going to try again with the 2 person method and will do the tappidy tap tap method as well. I also did feel the rotors when I noticed the wear. That one was they were all pretty hot (but that one may have been a bit hotter). Was worried that was doing all the breaking, but it does brake straight. There is some pulsating at low speed, but they do stop well. Just way to much travel.
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Old Nov 7, 2020 | 01:13 AM
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Interested in installing replacing front / rear brake lines with stainless steel lines. Have used Goodridge G-Stop kit on different vehicles in the past (believe kit # 21511 is correct for 06 - 2013) however, wanted to know If if anyone has installed / recommend a different manufacturer kit (Stoptech 950.44003 FRONT / 950.44504 REAR) etc.
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