I have a set of pads for an '87 XJ. Would I be able to install them on my '96 XJ?
ok, so let me see if I can remember all of this correctly, it's been a long time since I dealt with my D30. I wrote all of this down a while back, you can probably find those posts by searching my username.
Anyway.
There's not really any difference in the brakes until 97(?) I think, and you can even mix and match amongst those parts.
For instance, my D30 has
97 housing
97 shafts
87 knuckles
97 bearings
97 rotors
87 calipers.
As long as the bearings match the rotor the caliper does not matter.
As long as the pads match the caliper (early vs late) The year does not matter.
As long as the caliper matches the knuckle it will work.
I pulled the original CAD axle and gave it to lawncher, it was geared 3.07 so it was likely factory original. The brake calipers were identical to the XJ axle.
To my knowledge the only difference in the braking system between MJ and XJ were the rear brakes and the proportioning valve.
The MJ could be had with wider drums in the rear when ordered with the Metric Tonne package, or ordered with the tow package, or special ordered with the D44. Otherwise it got the same D35 brakes the XJ got.
The rear proportioning valve is also different, there was a weight sensing valve in the rear that limited how much fluid the rears got based on a linkage attached rear axle to bed. The proportioning valve up front is different to accomodate a third emergency circuit. So that if the fronts failed, it would bypass the weight sensing valve and sned full flow to the rear. It also takes to a disc brake swap pretty well.
Again, it's been a long time since I researched any of this, but that's what I remember. Search my posts regarding brakes from about 3 years ago and you'll dig up my thread with part numbers and cross references and the like.