brakes randomly went out

[famousguy_fsas]

so my brakes worked fine. until todat i started smelling them bad. and when i was driving my truck was pulling hard to the right. which tells me the right side wasnt decompressing or whatever. then when i pushed on the brakes they would pull hard to the left. and now my pedal will go all the way to the floor unless i pum them up knida fast. remember this just happened out of no where one second they were fine then BAM out of no where they were messed up. still filled with fluid which would tell me no leaks or busted lines. i need my truck

WHAT HAPPENED

 

[Broncobill78]

Does it pull to one side all the time now & does it worse when you hit the brakes or is it *just* when you brake ? If it's pulling hard to one side *and* you can smell them then I'm guessing that a caliper has frozen. It's clamped down on the rotor & the piston isn't retracting. Drive it around the block & then ck to see if one of the front rims is hot & smells. If it is that'll confirm the frozen caliper. It's a real easy fix, I just replaced both calipers on my 79' and they cost me all of $13 apiece plus $6 for brake fluid. Rear brakes don't generally cause the truck to pull so dramatically so I'm guessing it's a caliper. Not a big deal, you can replace both & be done with it for less than $50 (including new pads) and 2hrs of work. Check it out tomorrow & let us know what you find.

 

[famousguy_fsas]

yeah thats what i figured it was. it was pulling to the right when driving like the right caliper was stuck and when breaked weather it be just stopping or slamming it would pull real hard to the left. the funny thing now is my brakes work fine now.

so heres the story. after it started doing it i stopped and looked at brake fluid and it was fine so i put the top back on and nothing changed and still drove for another good 30 min. when i got home the breaks just went completely out. no pressure in the lines at all. so i went back and looked and i saw that fluid was coming out the top of the resivor like maybe i didnt put the top on right and it wasnt sealed. so i took the top back off and pushed the dimple thing in that is part of the big rubber seal thats located under the lid. really not sure what you call it but it was pushed out so i pushed it in. put the top back on and everything worked great. pressure came back and breaks didnt pull at all. so that explains the pressure problem. but the breaks pulling and being stuck started before i even took the top off. so whats the problem. or should i say what was the prob.

what should i look at to make sure it doesnt happen again?

 

[BroncoJoe19]

The slides or pins that the calipers ride on may need to be lubricated. THere is a special grease for them.

I also recently replaced my calipers, and was surprised that they were as inexpensive as they are. They really came down in price!

You are probably getting premature wear of your pads, and may be in need of a brake job anyway. Take a look at the pads, and plan on replacing your calipers when you do your brakes.

 

[Broncobill78]

I think Joe's got it, the caliper pins are probably sticking so that's an easy fix. On the other hand it's hard to go wrong for less than $15 apiece for rebuilds (*how* they're making money on those I don't want to know /emoticons/[email protected] 2x" width="20" height="20" /> )

 

[shift1313]

86 i think still had the old style slider. There is a guide thats held on with one bolt and a spring plate that goes on top. If this is stuck your caliper wont center and it will pull to the good side.

Also the diaphragm in the top of the cap is to allow venting. the cap is vented above the rubber diaphragm but you dont want the fluid vented to atmosphere, so if the fluid gets low or something that diaphragm can expand because it has atm pressure(14.7) on the outside and if its low on the inside of the res.

hope that made sense.

also pedal to the floor could indicate a vac problem. Check the rubber lines going to the booster and the check valve that goes between the vac line and the booster. This is a one way check valve. If its not working its possible at higher rpms you dont have any vac to help out.

 

[Broncobill78]

86 i think still had the old style slider.

"old style" my a$$. My 79' has those. I believe they're more properly referred to as "classic" calipers /emoticons/[email protected] 2x" width="20" height="20" />

 

[famousguy_fsas]

havent checked any thing yet but breaks work great. every once in a while ill hear like ametal sound but im gonna check that out this weekend. thanks all

 

[shift1313]

"old style" my a$$. My 79' has those. I believe they're more properly referred to as "classic" calipers /emoticons/[email protected] 2x" width="20" height="20" />

i keep forgetting. Sometimes when i look things up they are listed under vintage. feels weird.

 

[Mike G]

As for the peddle going to the floor I'm not to sure that a vacuum leak would cause that. It's still a mechanical connection to the master cylinder even without the vacuum boost. Mine was doing the same thing. Some days it worked fine the next I would hit the brakes and it would go to the floor and scare the **** out of me. Changed the master cylinder and fixed that problem. But a bad master cylinder would have no effect on the pulling unless it was so bad that it was sucking air past the pistons and down the lines since the master cylinder has one line for the front and one for the back brakes. Check for brake fluid between the vacuum boost and the master cylinder.

 

[BroncoJoe19]

My 90 has the "Classic" sliders in the front, and drum brakes in the rear with I guess "vintage" wheel cylinders.

When you do your brakes, and check the rears, do more than simply look at the pads, also peal the rubber caps back on the wheel cylinders to check for leaking, and push the plungers from side to side to make sure that the piston inside the cylinder is moving.

When I did my balljoints I did brakes up front, and replaced the calipers. When I took her for inspection, it failed for lack of rear brakes. To my amazment BOTH of my rear wheel cylinders were frozen solid!