Pulsating brakes solution?

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Ataxium

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So I've had a consistent pulsating issue with my brakes for a while now, they still function and stop as they should, other than the pulsing pedal.

Initially I thought it might have been bad calipers, so I replaced both of them. Pulsing persisted.
Over the last week I've replaced my entire front diff, and used the calipers that came with it.
Same pulsing still persists.

Rear brakes got new wheel cylinders a while back when I replaced my rear diff.

Trying to figure out my next move here, I'm thinking it's likely the proportioning valve. I've bled the absolute hell out of all 4 wheels and have a nice stiff pedal, I don't think it could be air in the system.
Or does this sound like it could possibly be the master?
 
You have a bent axle shaft?
 
Last edited:
Ataxium said:
So I've had a consistent pulsating issue with my brakes for a while now, they still function and stop as they should, other than the pulsing pedal.

Initially I thought it might have been bad calipers, so I replaced both of them. Pulsing persisted.
Over the last week I've replaced my entire front diff, and used the calipers that came with it.
Same pulsing still persists.

Rear brakes got new wheel cylinders a while back when I replaced my rear diff.

Trying to figure out my next move here, I'm thinking it's likely the proportioning valve. I've bled the absolute hell out of all 4 wheels and have a nice stiff pedal, I don't think it could be air in the system.
Or does this sound like it could possibly be the master?
Click to expand...
Typically the pulsation in the pedal comes from rear brakes, it shows up from the front brakes as a pulsating or shaking steering wheel when the front brakes have a problem. Rear drums are likely out of round or you have a bent rear axle.
 
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mrblaine said:
Typically the pulsation in the pedal comes from rear brakes, it shows up from the front brakes as a pulsating or shaking steering wheel when the front brakes have a problem. Rear drums are likely out of round or you have a bent rear axle.
Click to expand...
Mrholland said:
You have a bent axle shaft?
Click to expand...
I've got a 44 with discs that I'll be swapping in after October (insanely busy work month here in Salem). I guess I'll find out then if that's the case.
I don't want to bother fixing the drums now if I'm just getting rid of them in a few weeks.
If I had issues other than that minor pulse id be a lot more concerned.
 
So I just realized I left out one important detail that led me to believe it's the prop. valve.
The brake light has been on since this startded and beeps at me everytime I start moving from a dead stop.
 
So, over a year later I've finally gotten that 44 install and rear disc swap done. Took long enough, lmao.
Only issue is I'm still getting a pulse in my brakes. Everything under the Jeep is brand new at this point. So I can only assume its the proportion valve at this point. Will update when I finally replace that. Which given how much a procrastinator I am may be next year.
 
Ataxium said:
So, over a year later I've finally gotten that 44 install and rear disc swap done. Took long enough, lmao.
Only issue is I'm still getting a pulse in my brakes. Everything under the Jeep is brand new at this point. So I can only assume its the proportion valve at this point. Will update when I finally replace that. Which given how much a procrastinator I am may be next year.
Click to expand...

It is almost impossible for the combination valve to cause that.
 
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Ataxium said:
So, over a year later I've finally gotten that 44 install and rear disc swap done. Took long enough, lmao.
Only issue is I'm still getting a pulse in my brakes. Everything under the Jeep is brand new at this point. So I can only assume its the proportion valve at this point. Will update when I finally replace that. Which given how much a procrastinator I am may be next year.
Click to expand...

Did you get the dash brake light to go off?
 
mrblaine said:
Did you get the dash brake light to go off?
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It comes off and on intermittently. I believe it's related to the switch for the handbrake though, I want to say it has a bad connection because that light started coming a week after I installed an aftermarket radio and tried to connect it to the handbrake
 
Ataxium said:
It comes off and on intermittently. I believe it's related to the switch for the handbrake though, I want to say it has a bad connection because that light started coming a week after I installed an aftermarket radio and tried to connect it to the handbrake
Click to expand...

That light tells you when the shuttle valve has shifted when it thinks the system has a leak and has shut down or restricted the flow at one end. Without it functioning properly, it is going to be hard to tell what is going on.

According to what I can sorta figure out so far, there are no parts left in the system that were there when the pulsation started and it still persists.

Is that correct?
 
mrblaine said:
That light tells you when the shuttle valve has shifted when it thinks the system has a leak and has shut down or restricted the flow at one end. Without it functioning properly, it is going to be hard to tell what is going on.

According to what I can sorta figure out so far, there are no parts left in the system that were there when the pulsation started and it still persists.

Is that correct?
Click to expand...

Correct, everything on the underside of the jeep is brand new calipers, rotors, pads, lines, all of it.
 
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