I am a new owner of this wonderful truck. My auto repair experience is limited and I have brake failure. Before getting started I am hoping for some diagnostic direction. The brakes were working fine but went out quickly. The pedal feels as power brakes when the motor (or pump) is not running. It was low on fluid but adding fluid did not change anything. I am familiar with brakes on 50 chevys but not this F 350. I wonder about bleeding but if it had air I would think it would be by the reservoir and purge with gravity
My daughter described a clicking sound in the rear end when backing either of two trailers.

 

Welcome!pics of your truck will be in order lol

if the pedal is hard with the engine running then its mostlikely a vaccum pump issue.the vaccum pump is belt driven just above power steering pump
.get a vavccum gauge and check it when running.it needs 20" if memory serves me.

 

Thank you for the info, I would not have thought of that. I have to figure out where to check pressure. Does the pump look like a diaphragm or a sideways flying saucer?

I will be throwing up some pictures, I like my new buddy :-).

 

Welcome to FTE Yep, that's the vacuum pump! LOL! The hose that comes off of the pump runs over to the driver side inner fender to a vacuum manifold block. You can check it there. Just pull the hose off the block.

 

Is that 20" of mercury? Neither my water column gauge or magnehelic gauge go that high.

 

I found what you are describing. I took it loose over by the heater for easy access. There is vacuum but I don't know how much. I ran the engine to pull vacuum then used a stethoscope to listen to the hoses and could not find a leak. The vacuum is pretty good but without accurate measurement I can only speculate. Locating a gauge is my next task, I need to know what increments of measure, ie mercury? Can you advise me on that?

 

Hi Bill. Thank you for the advice and the kind welcome. I am new with the forum and just realized there was a second person helping me. I know to pay attention now. lol It is cool that y'all love these trucks, I can relate, I am hooked now. I have never even played with one until this purchase and even working on it is a joy. If I am not careful, I will be hoping for it to break :-).

 

It's measured in Hg (mercury) I think.

 

Yeah, we all love these trucks and most of us enjoy working on them.....but be careful what you wish for, you might end up like me

 

And you don't wanna b like bill...believe me.lol

 

It's not easy being this good lookin........

 

My guess is that your truck may have something to do with those good looks. lol

 

Is the brake light on your dash coming on? I didn't quite understand what you meant in the beginning. Is it "failing"likethe pedal gets super hard (bad vac pump) or failing like the pedal going all the way to the floor? Any fluids leaking?
And, btw, welcome to the forum!

 

No, the dash light does not illuminate it has in the past while at an idle and I have not found any fluid leaks but did add a substantial amount, maybe 4 ounces. The pedal does not go to the floor and is solid well above the floor. I have not had it long enough to know how it should feel but they initially have about 1/2 inch from resistance to solid. After it runs a minute it will pump up to feel like I would expect as normal, over an inch of resistance to solid but still almost no brakes. While I was crawling around I found a tee on the back of the rear end with a loose hose but the hose did not go anywhere.

 

That loose hose on the rear axle is the vent for the axle housing. It looks like it could be part of the brake lines, but it's not. My guess would be you either have a vacuum pump or a booster problem.