Brakes are terrible

[lariat 7.3]

Ever since i have owned the truck the brakes have been real spongey/hardly working. I replaced the master about 2 years ago maybe more. Didnt make a difference. I've bleed prob about a gallon of fluid through them and no change. Power steering pump is fine. Its been flushed. Pedal doesnt really do anything till it gets to that "rubber ball" feeling. If i keep my foot on the brake and shut the truck of it goes straight to the floor. Do i need another master?

 

[OBSWIZ]

Possible.....but you do need a set of SS lines.

 

[JLDickmon]

take the calipers off, and look at the wear on the pads..
not "how much is there," but more like are the worn evenly heel-to-toe?
I'm thinking you have a caliper stuck on one slider and it's flexing when you apply the brakes..

when you

If i keep my foot on the brake and shut the truck of it goes straight to the floor.

, this is the hydroboost unit dumping all it's pressure back to the PS reservoir

 

[lariat 7.3]

I feel like the master is just allowing all the pressure to bleed by it. Compared to the other 7.3's i've driven they have actual pressure on the pedal you can feel. Mine is just mushy and non existent. I've even service bled the ABS unit with my AE. Yes im sure the rubber lines are shot. 245k on them

 

[crowz]

I think the key to what you said in your first post is "When I cut the truck off the pedal goes straight to the floor."

THATS a bad master cylinder.

 

[ToMang07]

I agree, sounds like the master cylinder.

Did you bench bleed it when you installed it the first time?

 

[lariat 7.3]

yup bench bled it per the instructions, is there any difference between lets say an OEM ford one or The better quality parts place masters?

 

[Southmike]

you said you bled the brakes have you done a ps flush?

Charles found a master with more metal in it iirc. He had some sort of issue that fixed it
not sure who made it if it was napa etc. Maybe someone remembers

 

[lariat 7.3]

yep power steering system is in tip top shape, no whining or anything

 

[4.0l sahara]

Sounds like a master. There are no external leaks?

 

[wyomingtrucker]

I'm having the same issue with mine. Replaced everything on the rear end, new master cyl, new lines to the back, new push rod for the master cyl and flushed everything. Guess I'll change everything on the front now and see what happens. I'll let you know when I get it changed if the front calipers needed done.


Sent from my iPhone using Tapatalk 2

 

[4.0l sahara]

Also could be a stuck dump valve in the abs.

 

[lariat 7.3]

any way to get it unstuck?

 

[lariat 7.3]

no external leaks, put a brand new master in today. improved some not much though, pretty sure i have air in the lines though. didnt have a second person there to bleed them. Gravity bleeding wasnt really working

 

[rusty1161]

Try this http://motiveproducts.3dcartstores.com/0107-FordImport-Three-Prong-Bleeder-_p_117.html

The best bleeder I've used and you can do it yourself.

Rusty