Hello everyone! Need some help since i'm gonna be hauling my tractor around. When my dad past away a couple of weeks ago I didn't drive my truck for about a week for obviouse reasons. i'm only seventeen so its been a lil stressful with everything goin on but need to get out and do something. Anyways decided to take the truck out for a spin started up fine drove fine til I came to a stop sign. I guess I can the brake petal isn't supposed to drop to the floor and barely stop. Also notice that the front rotors were smoking after awhile. Decided to do some runs and slam on the brakes. I found that the front brakes are working overtime because the rear brakes aren't doin anything! There wern't even warm! So just today I decided to bleed the system since I had nothing else to do now that i'm off from school. Didn't really notice any major air but who knows. Took it out again to find that the rear is now stopping and brakes so much better. However, the petal still drops out. If I press and hold it, it just sinks all the way to the floor. Didn't do that before. I assume the master cylinder is shot but thought I should ask first. So any of yall know where I should start? Please let me know thanks!

 

Are you losing fluid? Did you check for leaks along the lines? The wheel cylinders could be leaking on the rear brakes, but you won't see that unless you take the drums off. The brake booster could be going, too.

 

Don't think its leaking havn't lost any fluid???

 

It's one of two things. Either the master is leaking internally or the ABS dump valve is dead. Can you pump the pedal back up?

 

If I pump the petal it will build pressure until I loose all the vacuum.

 

Sounds more like the dump valve, but the master is about 1/4 the price. Throw a master at it and if that doesn't cure it, replace the RWAL dump valve.

 

What year of truck is it?

 

Since his sig says it's a 250 I'm operating under the assumption that it's a 1st gen...

 

It's also possible the flex brake lines are collapsing and not letting fluid return, hense the over worked front brakes.

If replacing the MC and lines you might as well pump enough fluid thru the system to flush it with clean fluid. It's time on this vintage.

 

did first gen's have abs

 

Yes, on the rear wheels.

 

learn something everyday

 

"It's also possible the flex brake lines are collapsing and not letting fluid return, hense the over worked front brakes."

I'd do as bentwings suggested. Those lines collapse internally, look fine outside, but when you apply the brakes fluid pushes the shoes/disc and then the fluid can't return. Easy to fix and doesn't cost much either.

 

i think the collapsed lines are holding the front brakes on - making them overheat.


and the pedal going SLOWLLLLLY to the floor is a sign of the master cylinder being bad.

sorry about your father. if you need more advice, post up on here.

we'll be glad to help you. pray some (i do a lot that when i work on brakes)

put a hose on the bleed valve, put other end in a clear soda bottle, fill it up with water, then pump till clean fluid comes out

THEN start the bleeding process....

 

some stupid input here, but did u try adjusting the rear brakes? when my pedal gets sloppy, i just adjust the brakes and then its fine