On my 98 zj I just bought it had disc brakes installed with a ford 9" rear end. The brakes felt spongy like they needed to be bled when I bought it. I bled them and it didnt help, then I replaced the calipers, then I replaced the master cylender. The booster is good and Im thinking I need a bigger master cylender because it takes more fluid to squeeze discs than drums. Anyone know a larger master that would bolt right up? I heard one from a Ford E350 van might but Anyone know for sure. Thanks

 

the zj came with disks out back so your master is already set for that.

 

Really? My buddy has a grand cherokee also and his has drums in the back. Im pretty sure it had drums before the new rear end. The disc brakes on it are definitley not the origonals.

 

Is this ZJ built or did they just through a 9" in the rear for fun? Post up some pics!

Some ZJs had disc and some had drums. I believe 96-98 all had disc.

 

Its built. My buddy looked at it and said the rearend is actually a 9" curry high pinion. It has 35 spline axles. 6.5" long arm lift, HP dana 30 up front, 4.56 gears, lock right locker up front, detroit locker rear, ARB front bumper, custom rear bumber, rock sliders, gas tank and drivetrain rock gaurds, 33" mtrs, lights, etc...

I just need to figure out this break problem. Im pretty sure it needs a bigger master cylinder. Just curious if anyone knows of one that fits?

Did the rubicon last weekend and the steep downhill parts were a little scetchy. Ill try to post some pics.