Brakes are failing

[night9crawler95]

Drove the jeep all day today with no issues.

I have an 2002 3.7 6L automatic.

All of a sudden my brakes were hitting the floor and wouldn't stop the car.

Got home driving no more than 10mph on hazards lights and parked.

No leaking brake lines and master cylinder is filled to the max. No break fluid anywhere to be seen leaking out.

Pedal is hard when Lib is off but when it gets turned on the pedal hits the floor to the point you hear a metal to metal contact sound or grinding (what it might sound like).

Thinking I should bleed the breaks but no too sure. Please give answers. There is no way I can drive this thing anywhere.

CMEdge

 

[libertybob]

Brakes

With or without ABS brakes?

 

[night9crawler95]

No abs beeaks.

CMEdge

 

[twowings]

Inspect your front brake pads and see if you have any pad material left...that grinding noise may mean your calipers are into the rotors...when is the last time the brakes were serviced?

 

[megatone]

Possibly a bad brake master cylinder.

Push on the brake pedal and it is firm for a second or two then the pedal slowly goes all the way to the floor.

Common indication of a bad plunger within the master cylinder. One of two things could be happening:

You push the brake pedal, the brake fluid initially flows thru the brake lines towards the brake calipers then the fluid retreats past the brake plunger (in master cylinder) and back up into the brake fluid reservoir.........no loss of brake fluid.

You say there is a metal on metal sound....like grinding. Do you mean the sound happens when the vehicle is moving and you are trying to stop the vehicle or when the vehicle is stationary and you are pushing the brake pedal checking out how far it goes down.

Obviously, grinding noise while the Jeep is rolling while you push on the brakes would be an indication of severely worn brake pads. The only way for the brake fluid to get low in the reservoir is when the brake liner material gets low (grinds)....it's a trade off.

Since you say the brake fluid level is at MAXIMUM then I would think the pads are still good (unless ofcourse you've added more brake fluid to the reservoir recently).

You mention that the brake pedal is hard when the engine is not running....yeah, I don't doubt it.....it takes ALOT of leg muscle to push the pedal with the engine off. Try this: Get in the Jeep and push as hard as you can on the pedal with both legs and see if you can slowly push it to the floor.

The grinding noise you hear (if it happens with the car NOT rolling could be the brake piston scratching the wall within it's cylinder bore, which again, would indicate a bad brake plunger/master cylinder.

Could be a combination of bad brake pads (grinding) and bad master cylinder (pedal going to the floor).

Couple of good ideas

Good luck.

 

[night9crawler95]

Actually I just got new break pads a month ago and just replaced both front calipers. I have spoken to about 5 different people in passing and they all said master cylinder

CMEdge

 

[night9crawler95]

No I didn't top off the cylinder. No fluid loss and I'm actually picking up a MC right now

CMEdge

 

[profdlp]

Good luck, 'Crawler. :favorites13:

 

[megatone]

Where did you pick up the MC from? How much did it run you?

 

[night9crawler95]

MC is on and all is working now aside from my brake light just came on after installing it so I'm going to bleed all wheels tomorrow.

CMEdge

 

[megatone]

Good to hear you got the new MC installed. When bleeding the air out of the system, it might be a good time to completely flush (bleed) out all the old contaminated brake fluid. Doesn't take much more time than bleeding out the air. Brake fluid is cheap insurance against future contamination.

 

[night9crawler95]

Yup that's what I'm going to do.

CMEdge

 

[night9crawler95]

Where did you pick up the MC from? How much did it run you?

I'm sorry Mega I read your message and replied in my head. I went to Autozone and it ran me $46.99

CMEdge

 

[CactusJacked]

MC is on and all is working now aside from my brake light just came on after installing it so I'm going to bleed all wheels tomorrow.

CMEdge

You did bench bleed the m.c. before connecting it all up to the lines, right?

 

[night9crawler95]

Sure did.

CMEdge

 

[night9crawler95]

Still haven't bled my breaks yet and emergency break light is still on. I hope that after I bleed my breaks all will be well.

CMEdge

 

[night9crawler95]

Bled my brakes and my light is still on. Ebrake is all the way down and MC has just above the mac fluid.

CMEdge

 

[night9crawler95]

Still looking for some help. Issue has not been resolved.

CMEdge

 

[uss2defiant]

isn't the ebrake light issue just the parking brake sensor?

 

[night9crawler95]

isn't the ebrake light issue just the parking brake sensor?

From what I read it's the parking brake and brake fluid level sensor in the master cylinder.

CMEdge