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Adjust Rear Disc Pressure?

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Old Sep 1, 2009 | 08:05 PM
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Default Adjust Rear Disc Pressure?

Is there any way to adjust the proportion of brake power front to rear on the 01-04 trucks with disc brakes? I have to use considerable pedal before the rears will even start to grab leaving the front to do pretty much 100% of the work. I know this because I had the rear on jackstands and put it in drive, and to stop the wheels I had to push the pedal about half way down. They do not have air in the lines, so that is not the issue.

Before anyone says that its a bad idea and the rears dont do much anyway, I disagree since I am running large, heavy tires, the rears would help tremendously in reducing the angular momentum of the rear wheels even if they dont provide anything to stop the truck itself. Besides, if there is too much pressure on the rears, thats what ABS is for.

As I know of, these trucks dont have the typically proportioning valve, that its a premade unit cast into the brake distro block near the master cylinder.

Any ideas?
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Old Sep 1, 2009 | 08:28 PM
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I think that is not a good way to test them. Do your rear brakes look like new? I'll bet no.
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Old Sep 1, 2009 | 08:55 PM
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Hydroboost!!

jk..


put some new rotors/pads on the rear..
after i put new brakes on the rear of mine i cant even do a burnout, but i can build 10# boost
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Old Sep 1, 2009 | 09:31 PM
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brand new rotors, and pads look practically brand new

already have hydroboost

why is that a bad way to test them?
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Old Sep 1, 2009 | 09:57 PM
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i wonder the same thing cause in my truck i can barley tell the rear brakes are doing much until im gettin on the pedel hard and the pads are practically new?? is it just the way its proportioned factory?
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Old Sep 1, 2009 | 10:15 PM
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I guess so.... my fronts instantly grab, but it takes considerably more pedal movement to engage the rears. This also has the effect of making my fronts do all of the work and dust up my wheels pretty good while the rears stay perfectly clean, which tells me they arent doing anything at all unless the pedal is on the floor...
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Old Sep 2, 2009 | 07:06 PM
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....am I the only one with this problem?
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Old Sep 2, 2009 | 07:08 PM
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My brakes suck ***.
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Old Sep 2, 2009 | 10:47 PM
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I believe that the factory proportioning is something like 70% front, 30% rear, so what you're explaining sounds like normal operation to me. As for brake dust, if you look at just about any vehicle, the front wheels are usually considerably dirtier than the rears, whether it be 4 wheel disc or rear drum.
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Old Sep 2, 2009 | 11:01 PM
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Normal operation does not mean best operation, and we all know once you start changing things, like say putting on bigger tires, other things need to be adjusted as well.

If normal is 70/30, how can I make it, say, 65/35?
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