Hey guys so yesterday my 94 xj 2dr started acting weird. When i begin slowing to a stop occasionally i will lose all resistance in the brake pedal and ill have to pull the emergency brake and smash on the brake pedal to the floor to get any braking. The mechanic that did some work a few weeks ago told me my front brakes and rotors need to be replaced but this seems like a different problem. It doesn't happen all the time but it seems to be increasing. What should i do? I was going to replace the front pads and rotors soon anyways but maybe ill go ahead and order some now?

 

Your master cylinder is wearing out. It will need to be rebuilt, or as more common replaced. The time to do that is when you do your front brakes, which should be soon. You don't want to hit something.

 

Master cylinder??? Ill do some research.

 

Im looking to upgrade to high quality brakes and rotors so while im at it i would like to upgrade anything else brake wise on a stock 94 xj. You guys have any recommendations?

 

I have these so far what do you think?

Disc Brakes Australia Front 4X4 Survival Street Series Gold Drilled & Slotted Rotors for 88-99 Jeep® Cherokee XJ

Hawk Performance Ceramic Front Brake Pads for 90-06 Jeep® Cherokee XJ, Grand Cherokee ZJ, Comanche MJ, Wrangler YJ, TJ & Unlimited

Brake Master Cylinder for 90-94 Jeep® Cherokee XJ with Power Brakes

Power Brake Booster for 91-94 Jeep® Cherokee XJ without ABS

Crown Industrial 5 Layer Custom Extended Brake Lines in Red for 90-01 Jeep® Cherokee XJ & Grand Cherokee ZJ with 3-4" Lift

Old Man Emu Nitrocharger Steering Stabilizer for 84-06 Jeep® Cherokee XJ, Grand Cherokee ZJ, Wrangler YJ, Wrangler TJ & Unlimited

DELTA® Rectangular H4 Headlight Conversion Kit with Xenon H4 Bulbs for 87-95 Jeep® Wrangler YJ & 84-01 Jeep® Cherokee XJ

Mr. Grille Billet Grill Inserts in Black for 94-96 Jeep® Cherokee XJ

the last two are not needed but wanted!!! )))

 

If you want to do an upgrade, I would suggest a couple of things. First try to find some ceramic brake pads for the front. They are extremely fade resistant and last a long time. I have then on my Subaru and they not only stop better than stock, but smoother and don't change their stopping ability when the brakes warm up or get hot. The second thing is a popular upgrade is the ZJ brake booster. It is double diaphragm and will apply more force to the brakes with the same brake pedal pressure you are using now.

 

Hm is this what your referring 2?

Power Brake Booster for 95-98 Jeep® Grand Cherokee ZJ

 

Yes. There is a slight push rod modification that needs to be made, but otherwise a bolt in. You can search for the upgrade here or on NAXJA it has been done numerous times.

 

Really bad rotor(s) knocking the pistons back in the caliper could masquerade as a bad master cil. Does it always pump up hard after a few? Does it stay that way? Until you drive a bit? In other words, if you calmly pump it a few times, will it come back hard? A common master cilinder failure is fading, the pedal continuing down.

Not to distract from the good advice you are getting....you might do the rotors ect. first, then somehow test it without crashing!

 

Ok wow great point when it happens no matter how many times i pump the brakes i don't get them back. I have to drive a bit and occasionally i will sometimes have brakes. BUt its getting worse.

The mechanic said my rotors were real bad so it doesn't make sense to replace pads.

 

Sounds like you should park it and replace at least the master cil., rotors, and pads.

 

X2

 

[QUOTE then somehow test it without crashing![/QUOTE]

X10

 

Are you loosing fluid? Is the resivoire still full? Could be a blown REAR wheel cylinder, or some other loss of hydraulic pressure. If there are no leaks in the system and the res is still full, it's almost deff the master cyl.

 

UPDATe. Replaced master cylinder brake rotors and pads for $250 installed. Thanks for the help guys. The master cylinder was leaking oil into the brake booster.. ouch..And my rotors and brakes were at the dead end pretty badd..