Horrible Braking

[Dino76033]

I have a 2004 Rubicon I recently purchased and I'm not digging the brakes. I have replaced pads, rotors and bled the brakes. I drove my Dads 2002 TJ with drum brakes on the rear and it stops great. Both Jeeps are on 33's with 2" lifts. It feels like I don't have power brakes. You really gotta press the pedal. Any ideas?

 

[TheBoogieman]

Make sure the calipers aren't sticking and bleed them again. I can lock up my 35s when needed.
p.s. You should have bought Black Magic brakes.

 

[Dino76033]

I used a vacuum pump to bleed my brakes yesterday and flush all the old fluid out. The fronts bled like normal. The rear however (both sides) had air bubbles that would not stop coming out even though I was clearly at the new fluid. I have no leaks anywhere. Would that be a master cylinder issue?

 

[mrblaine]

I used a vacuum pump to bleed my brakes yesterday and flush all the old fluid out. The fronts bled like normal. The rear however (both sides) had air bubbles that would not stop coming out even though I was clearly at the new fluid. I have no leaks anywhere. Would that be a master cylinder issue?

The problem with those piece of shit vacuum bleeders is there is not an airtight seal between the bleeder threads and caliper body. That means it will suck air in through the threads and give you the impression that you are still getting air when you may or may not be. So no, the master is not bad due to seeing air.

 

[Rubicon88]

Don't use a vacuum pump.

We make brake lines all the time thus have to bleed systems.

Your issue sounds like it could be....a couole of things...

your extra hard pedal/lack of brake strength be a bad brake booster/vacuum thereof

Or

Line obstruction (pinched line/debris inside a line or caliper (s) which I doubt is the



As far as bubbles spewing out the back and not the front....

Let's ask some questions.

Did anyone including you mess with any of the lines? Any leaks even if slight in the system?
Has the master cylinder fluid level ever gone dry or very close to it?

 

[mrblaine]

Don't use a vacuum pump.

We make brake lines all the time thus have to bleed systems.

Your issue sounds like it could be....a couole of things...

your extra hard pedal/lack of brake strength be a bad brake booster/vacuum thereof

Or

Line obstruction (pinched line/debris inside a line or caliper (s) which I doubt is the



As far as bubbles spewing out the back and not the front....

Let's ask some questions.

Did anyone including you mess with any of the lines? Any leaks even if slight in the system?
Has the master cylinder fluid level ever gone dry or very close to it?

It is hard for the average person to differentiate between a hard pedal due to low or no vacuum assist in the booster and shitty brake pads that aren't working very well which require lots of pedal effort.

 

[Dino76033]

No vacuum leaks that I can find.
There is good vacuum at the booster.
All lines look good with no leaks.
I bought the jeep a couple months ago so I'm unsure what the PO had done.
The master cylinder was pretty low when I got the jeep but so were the pads.
The rotors and pads are Centric. Ceramic pads.

 

[Dino76033]

Is it common for a booster to go bad?

 

[Rubicon88]

No vacuum leaks that I can find.
There is good vacuum at the booster.
All lines look good with no leaks.
I bought the jeep a couple months ago so I'm unsure what the PO had done.
The master cylinder was pretty low when I got the jeep but so were the pads.
The rotors and pads are Centric. Ceramic pads.

How do you know it's good vacuum there?

 

[Rubicon88]

It is hard for the average person to differentiate between a hard pedal due to low or no vacuum assist in the booster and shitty brake pads that aren't working very well which require lots of pedal effort.

Well...I've covered many times the people that just "did a brake job" and most...(Not all) but most really have no idea what they're doing.
Jam the pads on and crack a beer..."they just did a brake job"

 

[Dino76033]

How do you know it's good vacuum there?

Just by feel of the finger.

 

[Rubicon88]

Just by feel of the finger.

Ok....
Have you seen a difference if you remove the booster out of the equation?

 

[Dino76033]

Meaning remove the vacuum then go drive it? If so, I haven't tried that.

 

[Rubicon88]

Meaning remove the vacuum then go drive it? If so, I haven't tried that.

Don't even need to do that. Just at idle you should feel a difference with and without.

 

[03coloradowrangler]

how old are all the rubber flex hoses on the brake lines? I remember driving a 60's car with the original rubber hose to the clutch slave cylinder and had issues with the clutch slipping a few seconds after disengaging the pedal due to the hose swelling. a new hose solved the slipping problem.

 

[Dino76033]

Don't even need to do that. Just at idle you should feel a difference with and without.

There is a definite difference when unplugged. I guess that rules out the booster.

 

[Rubicon88]

There is a definite difference when unplugged. I guess that rules out the booster.

Correct

 

[Rubicon88]

Next you need to check if there is obstruction with your lines/calipers