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Symptoms of a failing brake booster and master?

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Old 09-26-2013, 07:22 PM
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Default Symptoms of a failing brake booster and master?

Before I changed my front brakes they really bad. It had slow and weak stopping, and when I towed 5k last it seemed like they were barely there. I recently upgraded to dual piston calipers, new pads and new discs as well and in the process I was expecting my brakes to be like new. My truck does have the hydroboost set-up.

With the new set-up the brakes are better, but they are not good. I feel like there is just not enough pressure. One caliper has slightly more resistance than the other. The brake pedal is very firm and feels good. When I was pumping the brakes to bleed them I did notice a hissing type sound coming from them booster/master cylinder. When I had someone else pump the brakes I noticed in the rear of the reservoir there was (I want to call it bubbling, but I'm sure there was no air) fluid movement, that seemed like a small fountain trying to take form.

From what I have read online, it seems as if either my Master cylinder or hydroboost is the cause. Around my hydrobooster there is fluid all over it (not leaking with an amount that can drip, but sweats). Does it sound like the problem of having weak brakes is one or both of those parts?
 
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Old 09-26-2013, 08:16 PM
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You are describing a hydro boost seal failure ... best to get a new unit ... before it comes apart in a needed time ... it sounds like its continuaslly bypassing fluid and not buildint pressure or vaccum in the booster...
 
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Old 09-26-2013, 09:27 PM
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Originally Posted by 4x4manonbroke
You are describing a hydro boost seal failure ... best to get a new unit ... before it comes apart in a needed time ... it sounds like its continuaslly bypassing fluid and not buildint pressure or vaccum in the booster...
Thanks for that. I also forgot to mention that the brake pedal does have a slow return as well... I will plan on replacing the hydroboost unit then!
 
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Old 09-26-2013, 09:34 PM
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i would go booster and hydro .... better safe than sorry ... cheep insurance ... as cheep as the parts can get anyways .....

check on line prices ... rockauto.com, autoanything.com ...ect..
 
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Old 09-26-2013, 09:59 PM
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I found this site: New 1994-1999 Dodge Truck Ram 2500, 3500 Hydro-Boost Brake Booster 1.250 Master Cyl, Cummins Diesel

Looks like a pretty good site? and let's you customize. Have you heard of them at all? or are they overpriced?
 
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Old 09-27-2013, 03:21 PM
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Good company .... have gotten parts from them before ..... wow ... hydro is cheep for a dodge ...... might have to swap mine ......
 
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Old 09-27-2013, 04:00 PM
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Check the adjustment of your rear brake shoes. I had a similar issue, I burnt up my brakes coming down a hill with a heavy load and changed front brake pads, rotors, hydroboost and mastercylinder (they were seeping and needed to be replaced), and bled the system and had poor stopping power and poor pedal return. Come to find out the rear brake shoes had disintegrated leaving a huge gap between the brake shoe frame and the drum. You should adjust the shoes until just a light drag is felt. Also note that the rear brakes self adjust when you apply the parking brake (assuming all the springs and such are working properly) so you need to use it once in a while.
 
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Old 09-27-2013, 06:17 PM
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Thanks for the advice! My rears are good though I put in new shoes and wheel cylinders about a month ago, and use my e-brake everytime I park. At least now I'll remember to be cautious of checking that.
 
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Old 09-27-2013, 09:02 PM
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Originally Posted by RedChevy44
Check the adjustment of your rear brake shoes. I had a similar issue, I burnt up my brakes coming down a hill with a heavy load and changed front brake pads, rotors, hydroboost and mastercylinder (they were seeping and needed to be replaced), and bled the system and had poor stopping power and poor pedal return. Come to find out the rear brake shoes had disintegrated leaving a huge gap between the brake shoe frame and the drum. You should adjust the shoes until just a light drag is felt. Also note that the rear brakes self adjust when you apply the parking brake (assuming all the springs and such are working properly) so you need to use it once in a while.
Good advise Red ..... will keep that in mind .... im wondering ... gonna be a bit of work to go from vaccum brakes to hydro ...... ... wonderin if i should do it ... probably not worth it sisnce i only haul ***
 
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Old 09-27-2013, 09:59 PM
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Originally Posted by 4x4manonbroke
Good advise Red ..... will keep that in mind .... im wondering ... gonna be a bit of work to go from vaccum brakes to hydro ...... ... wonderin if i should do it ... probably not worth it sisnce i only haul ***
Last I checked.. hauling *** still qualifies for hydroboost! If you ever look back and see 5-0 you're going to need more pressure to drop that speed fast!
 



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