Rear disc brake swap for XJ question
 

Thinking about doing the swap. I know my rear drums have never been changed since I've owned my XJ. It had 125k on the clock when I bought it in 07 and now it has 193k. There's a grinding noise back there when it's been sitting for a while but it goes away after they warm up. Still I think it may need new shoes regardless of type. It has a Dana 35c rear axle. Which is the easier swap or are they both about the same? There is the 2007 KJ Liberty rear discs and the 1998 Grand Cherokee ZJ discs? I've not read any comparison of install between the two setups. Anyone have some info on it?

I would say the two swaps are about the same. The Liberty
cables work with both if you want to keep it simple.

If your XJ is just street-driven and you are satisfied with the
stopping power, then just change the shoes, adjust them, and
go on.

If you go offroad in the mud and want cleaner rear brakes, or
if you really want more stopping power, discs should help.

If you have a 1994 or older XJ then you can gain significant
stopping power by swapping in a 95-96 dual diaphragm booster.

Let me just say that I swapped in ZJ discs and I am in the sand
and mud a lot. The ZJ parking brake gets gummed up every month,
and that is a problem because I have a 5-speed and need it. The
XJ parking brake wasn't much better.

I have a 96 XJ 4x4 and it is a DD with virtually no off road usage. I was looking at replacing the rear drum brakes myself but it looks like a PIA to do. I've read the KJ swap is easier because everything is pretty much a straight swap over. For the amount of money to get the rears done I could probably get what I need to get the KJ parts.

It's really not that hard and there's plenty of pictures and diagrams out there to help with rebuilding them, if you have the mechanical know how to swap on disc brakes, you got the know how to rebuild drums. I rebuilt both rear drums down to the backing plate (Hardware, Shoes, Wheel Cylinders) with Raybestos parts though Rock Auto for less than 70 dollars. The local brake shop turned my OEM Chrysler drums for another 20 bucks.

Relevant question: I will suck up my embarrassment and admit I just had a brain freeze out in the garage and pumped my brakes with the rear drums off. Heard a "pop", and now I have this:

https://i.postimg.cc/zfz4pkHD/IMG-20...-163811702.jpg
https://i.postimg.cc/dVmz8f1S/IMG-20...-163817005.jpg

I am pretty sure I broke something in the cylinder, but I am not sure what to do or how to troubleshoot/fix. Anyone have thoughts? Had not planned to switch from drums to rotors, but now I suddenly might have a reason...

You probably just need new brake cylinders.

Yeah, I think you are right. The cylinder is clearly in need of replacement on that side now. Thanks