HELP PLEASE!!!!! Brakes are all rear!

[mengquis]

So I was driving around yesterday and then all of the sudden the pedal went ALMOST to the floor with little feedback.

I babied her home safely and adjusted the rear brakes this morning. BETTER! But still ALL rear braking. Very little front brakes and still pretty spongy. ANY ideas?????

The truck is a 01 Tundra, v6 2wd. Nothing special, 210k miles.
Recent maint: Got a brake light, replaced the brake fluid in res with new dot 3. Still has a green tint to it. Light went out. ANY help would be of GREAT appreciation!

[Thundra04struck]

Have you taken the front wheels off to look at the calipers/brake lines at all?

See if there is any brake pad left or if a line has ruptured or is leaking?

How about looking under the hood at the master cylinder and the metal lines going to the front brakes?

You could have blown out the master cylinder.

[kovawa]

210K? I'm betting it needs a new master.

[mengquis]

I did a visual on all the brake lines, no problems seen. No fluid lost anywhere.
Just bled the brakes, nothing major to report. Bled the prop valve as well.

Still just as bad! No front brakes at all. Brake pedal WILL hold pressure, no leak down at all.

[santi2322]

Agree with the above.. your master is probably shot..

[kovawa]

I did a visual on all the brake lines, no problems seen. No fluid lost anywhere.
Just bled the brakes, nothing major to report. Bled the prop valve as well.

Still just as bad! No front brakes at all. Brake pedal WILL hold pressure, no leak down at all.

When you say it holds pressure- are you stomping on the pedal or just gently resting your foot on it? I ask because - many times a failing master cylinder will feel as if it's working properly when you stomp on it. But if you gently apply pressure to the pedal it will slowly sink to the floor. This is due to the fact that sudden application of the pedal has enough force to make the o-ring seals move and make a tight seal. Slow application of the brake pedal allows enough time for the brake fluid to leak past or "bypass" a worn o-ring and results in the "spongy pedal" when braking normally.

[mengquis]

So update!
Changed master cylinder, bench bled before install and everything. Bled all 4 wheels and proportioning valve. No change. Still sucks!

I did notice that i had microbial growth in the old reservoir (hence the green tint) and replaced with new res.

Still no idea what is wrong!

[doubleds65]

Did u check 4 leaks on the pistons in the caliper?

Sent from my HTC_Amaze_4G using AutoGuide.Com Free App

[mengquis]

Yep! Just checked that, no leaks

SO here is where I am at after working all day on it:
master cylinder changed
brakes bled to NEW fluid flowing through with no air
Brakes inspected for operation:
So here is where I found something interesting------Brakes only move a little and pedal locks up before hitting the rotor. NO braking available with engine off and pedal is SUPER firm!
I moved the front left pads away from the rotor 1/4" and with engine off- the pedal locked up and no more movement after 1/8"
Clunking noise heard when pushing pedal all the time.

[SuckersWalk]

after replacing the mc assuming you don't have any leaks as you state, my money is on either air in your system or you have a problem with your proportioning valve or your new mc isn't functioning property. likely your new mc is fine since you have the same problem now as you did with your old mc. personally, i would hit up the Brakes sub-forum and take a look at this How to Troubleshoot Brake Problems - For Dummies and this http://www.mpbrakes.com/uploads/docu...hootingpdf.pdf . you may just want to stop working on your not working brakes and find someone that can stop what they are doing and stop by your house to fix your brakes for you so you can stop pulling your hair out

[tundrunk]

Booster? Interesting that the pedal hits floor before the pads hit rotor.

[SuckersWalk]

that would be easier to understand tham if he had a firm pedal and still no front brakes i guess. then i would suspect the adjustment he did to his rear brakes needs to now be backed off just for ****s and grins

[Thundra04struck]

You said you " . . . moved the left front pads . . . " so that means that at least those locating pins for the brake pads are not seized up, preventing the pads from moving anywhere.

I had an issue where the pins were seized in the caliper causing me to have to pump my pedal twice to get good braking action, otherwise the pedal was very soft. Probably not the issue but worth looking at

I have heard about the need to bench-bleed the MC before install as air can get trapped in them and regular bleeding doesn't work the air out.

[burned300]

Forgive me for not knowing, but does an 01 have anti-lock? if so, when bleeding you never want to let brake system get any air. MC need to stay full at all times. I've seen were people have just let all their fluid out & go to refill, and air gets trapped in the anti-lock system.