need help with rear disc conversion

Ok, So: I installed ZJ disc brakes on my 97 XJ Chrysler 8.25 today. I have no pedal. There is hardly any pressure on my rear brakes at all. IF I slam the pedal to the floor the front will nearly lock up and the rear floats to the sky because of the nose tuck. It is dangerous to drive on the highway as it sits so I need help fast. I have read a couple of articles but still would like some input.

I have also installed the ZJ proportioning valve. So, stock fronts, ZJ rears. No leaks, and I bled over 2 1quart bottles through the lines today. PLEASE HELP ME!

I did use the search function first, but didn't find answers for a direct zj swap that caused a loss in pedal.

you positive the calipers weren't installed backwards?

I had a very squishy pedal right after the swap, found out one of my lines was leaking and after bleeding it a few times it burst. After that, was better, then a few break in runs brought it right back.

best of luck

Yeah, are you sure the bleed nipples are at the top? If they are not at the top, you will never get it bled.

bleed the whole system, starting with rear right, then rear left, front wright, front left, you must not allow your reserviour get empty, so make sure you fill it once a while, and I would get rid of old fluid before bleeding......

XJ-nick said:

Ok, So: I installed ZJ disc brakes on my 97 XJ Chrysler 8.25 today. I have no pedal. There is hardly any pressure on my rear brakes at all. IF I slam the pedal to the floor the front will nearly lock up and the rear floats to the sky because of the nose tuck. It is dangerous to drive on the highway as it sits so I need help fast. I have read a couple of articles but still would like some input.

I have also installed the ZJ proportioning valve. So, stock fronts, ZJ rears. No leaks, and I bled over 2 1quart bottles through the lines today. PLEASE HELP ME!

I did use the search function first, but didn't find answers for a direct zj swap that caused a loss in pedal.

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Did you replace the entire Proportioning valve or just the innerds?

With my rear disk setup I installed the calipers upside down at first. It took me forever to figure out why I could never get a firm pedal, months later I realized the bleed nipple wasn't on top and I finally switched them.

Needless to say, check that first followed by pulling off the O-ring on the prop valve. Mine has great stopping power with 33s, 4.88s in 4low and first gear.

Also be careful bending those original hard lines on the rear axle, I bent mine for the install and 3 months later I blew a hard line near one of the bends (it wasn't bent hard either) the morning of a trip to go wheeling... ya it sucked.