Ok so I was trying to do some research on here before posting but I am still somewhat confused. I have pretty soft and squishy brakes on my 91 F250. Its been sitting a while and I am in the process of getting it back up and running. When I started working on the truck the brake reservoir was empty so we filled it and bled the brakes. I am not going to say their ISNT any air but we cycled out the remainder of the old fluid from the all the brakes and did a bunch of father son brake bleeding. The rear cylinders and the front calipers so they seemed pretty good. Anyway I still have pretty squishy brakes. I do get the whooshing noise that I take it is from the booster. I haven't had any issues with hard brakes? I also dont think there is a hiss just the woosh from hitting the brakes. So I have also read the master cylinder is generally the cause of the squishy brakes. Where I get confused is the woosh normal or is that a sound to be concerned with. If I am driving along and haven't used the brakes in a while they seem super soft but they do firm up if I pump them a little. It is very disconcerting in the process however, and I am not comfortable towing yet until this gets worked out. We were out on some dirt roads today with some heavy use of the brakes and I got really nervous as they were super soft but they still worked. Again got a little better with pumping.

Thoughts? Master Cylinder or both Master and booster?

 

getting a little better with pumping tells me you still have air in the system.

 

I should clarify the brakes are soft but fine under normal conditions it was the excessive use off road that I really had to pump the brakes and they were hot. I am willing to concede that there is most likely still air in the lines.

I want to change the old lines for SS anyway so I'll get to do another round of brake bleeding soon regardless.

 

complete SS line kit is about 200 bux..... the Labor is another story

 

screw stainless lines. i use the epoxy coated alloy lines.
they last forever, and i can do a complete truck for under $80

 

yepper... I won't waste my time with stainless when Copper Nickle is so easy to use..... BUT some folks just want that Stainless aggravation

 

The main hard lines are fine. The only place I am looking to use SS lines are to replace the old flexible hoses. So if you have some magical flexible copper nickel lines I would be interested in learning the ways..

 

you said "I want to change the old lines for SS anyway" you never said "Flex Lines" .. and BTW I want to see these all "Stainless Flex Lines"... that won't happen only will have a protective Braid.... but anyway make sure you get lines that have a PVC jacket so dirt and such doesn't get into the braid as this can cause early failure.

 

Ookay... Thanks