What does it mean if you suddenly lose braking pressure?


juntjoo

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Never had this happen to me before. I was working last night which involves starting and driving my truck shortly, turning it off then repeating. And suddenly after starting it one time I find my brakes spongy and that I've got very low level of fluid in the MC. I dont have the truck on me, I left it at work and will ride my motorcycle to it today to work on it. I read somewhere it could have to do with some auto setting drum brake function that you can remedy by pumping the brakes while going in reverse, which I'll try first which would be great if it works, but if not would this most likely be some sort of failure somewhere in the system like a leak at some point that just suddenly busted? That's what I'd imagine although from a quick check with my phone camera(wasn't willing last night to wiggle my body under the truck) I didn't see any obvious fluid having leaked. I guess I'm hoping like the drum brake quick fix there might be something else(if not the drum brake system) that just fell out of order that won't require replacing any parts and I won't have to trap my tool box to my bike.

What are the top most likely situations I've got going on here? I am going to bring as many tools as possible just in case, but just wanted to get a better idea of what I could be dealing with. Thanks!
 


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Uncle Gump

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Sounds like you have a leak... maybe popped a brake line or hose.

A quick visual of said lines and hoses underneath the truck will probably identify the problem.

Fill the master cylinder first... pump the brakes several times then do your visual inspection... probably see it dripping.
 

juntjoo

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It's related to the MC if the whole braking operation is affected correct? I just read it's a "split system" meaning if there were a problem like a leak in either the front or rear brakes then the other half would operate normally and you wouldn't get such loss(85%ish)in functionality correct?
 

Uncle Gump

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Short answer... yes

In reality... the pedal goes straight to the floor with very limited brake in opposite axle. It's bad enough that you will park the truck and find a way to get home as you did last night.
 

RonD

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Yes, I agree with Uncle Gump

Broken brake line fits the description of what happened, spongy then pedal to the floor

Rear brake line runs to the back inside the driver's side frame rail, not uncommon for it to rust thru and leak between gas tank and frame rail, I have had two Rangers do that.

As said fill Master and pump brake pedal then look for the wet spot under the truck



Most vehicles have "split" brakes, but pedal still goes to the floor, you can pump it and the system without the leak will still work until pedal gets down to the floor and you have to pump again.
So you are not without brakes, just without good brakes
 

juntjoo

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http://imgur.com/a/rZXT7qj

For some reason the 2x4 calls for the wrong part, the one pictured. It's too long. Looks like it rubbed against the wheel. And it doesn't mount right. PO used a zip tie. Turns out the 4x4 part fits perfect. Anyway, all fixed now.
 

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Glad you got it fixed. Thanks for the update.
 

Uncle Gump

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That will do it everytime... good to hear it's rolling down the road and stopping.

You have the 4wd suspension on your 2wd truck. Torsion bar opposed to coil spring. Might want to keep that in mind when buying front end parts.
 


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