# Brake Problems F-350



## aperfcrcle (Feb 9, 2010)

I just replaced my tires (all 4) and my truck is now all of a sudden acting up. I got it back and the first thing I notice is my brake pedal is going all the way to the floor. Before this my brake pedal was nice and stiff, but nowt it just keeps creeping to the floor and I feel like all my stopping power is gone. If I sit at a light with it down, it just keeps sinking further. Then to top it all off, my brake light comes on the dash. The one time I take it to go get something done is the only time I have EVER had a problem with this truck.. go figure. Its a 2002 Ford F-350 7.3.. I checked the master cylinder level and its a bit low, but i really cant see that being the problem. Help me out


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## MickiRig1 (Dec 5, 2003)

Have a helper pull the top off the master cylinder when you have the brakes pushed down. Have them watch for fluid coming back into the reservoir. Look for drips under the truck too. If you have fluid coming back into the reservoir the cups on the master cylinder may be shot. Look close under the truck. It's not unheard of having both brake circuits have lines pop. I have had two trucks that have done it.


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## geer hed (Nov 22, 2010)

If your pedal is dropping there is only a couple things it can be. one is air in the lines, but this usually causes a spongy feeling. If your loosing fluid there is only 3 places for it to go, on the ground, on the floor board, or into the vacum advance canister. the first two will be pretty obvious. the third is if you add fluid and watch it drop with out doing a thing, the seal between the master cylinder and vacum chamber is bad.


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## bbirri (Nov 6, 2010)

if it sinks down with steady pressure and u have no leaks = mastercylinder


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## Luke_P (Sep 16, 2008)

micks advice is good both lines could go, have seen it very uncommon, master could have gone, also uncommon but micks advice on how to check is good, considering you just had tires put on and your trucks age I would say somone disturbed a brake line either with a jack or trying to knock a tire off who knows maybe just coincidence, as previousily mentioned look for ovbious leaks to narrow it down try this 

your rear brakes are activated first as you push down on the pedal. you say you can get to the floor but is the pedal stiff for a bit then soft? try pushing the pedal down very slowly if you can get some resistance (untill about 1/4 to 1/3 of the pedal stroke then it gets real soft suspect a problem in the front circuit. the opposite is true if your pedal is very soft then gets hard all of a sudden (about 1/4 to 1/3rd of the way again) fronts probably good look for a leak in the rear. as you say you can get to the floor i would suspect the front circuit is leaking also pull your tires and look for leaks at the caliper (pistons) they are not always real ovbious


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## deicepro (Mar 24, 2009)

Just had a similar problem with one of my F450's, turned out it was the master that went bad


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## MickiRig1 (Dec 5, 2003)

When you push the brake pedal it goes past the inlet holes. So any movement of fluid in the reservoir after that means the fluid is leaking past the cups. Or it's going somewhere. The surface in the reservoir should be dead calm no movement of fluid at all. I would not think the anti-lock system would be the problem. It will throw a code and light the brake light. Make sure when you start the truck the light does come on to check the bulb. Or push the parking brake down a few clicks.


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## aperfcrcle (Feb 9, 2010)

hey guys, thanks for all the help. The problem became quite obvious this morning when there was a puddle on the ground. I followed it up to a brake line on the drivers side by the rear. Took it to the mechanic and he had to replace the whole line going back. It was quite expensive and I think i got ripped off but atleast I can stop now.. $150 for the job.


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## MickiRig1 (Dec 5, 2003)

Bummer, If one of us did it the job would of been about $30 for parts or less.


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## aperfcrcle (Feb 9, 2010)

MickiRig1;1155054 said:


> Bummer, If one of us did it the job would of been about $30 for parts or less.


$40 for the parts and over a hundred for "install and bleed"


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## suzuki0702 (Apr 6, 2008)

30 for parts,30 for bleeding, the rest for beer!


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## Luke_P (Sep 16, 2008)

if it makes you feel better i had a rear line go while i was at my sister in laws a few years back in one of my older trucks. there was a shop around the corner told him what it needed size of line and length(i already crawled under and looked) and he said $200 i knew it was a kick in the nuts especially since i had a roll of line at home but i thought a tow would cost me 150 plus i still have to go under it and do the work ok go ahead. he did it and it worked but you would think as i seemed a little more educated on the subject then some he would 've done a good job, he didn't. He didn't even pull the old line out just tie-wrapped it to the old one. looks like sh!t and is more exposed to the elements. I did the same job on the same model truck about 4 months later took me an hour with a extra set of hands to do it properly, needless to say ill pay the tow next time.


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