Difference in older ('88?) D30 axle shaft flange depth?

[CameronB]

Picked up a built D30 from an '88 MJ for my '95 XJ, and my EBC Rotors and Calipers won't fit... the mounting flange on the shaft puts the rotor into the knuckle too far. Also, my brake pads won't fit on the knuckles. These older knuckles have a bolt-on style of mounts for the brake pads, instead of being cast into the knuckle.

So I'm thinking that I'll have to swap knuckles and shafts from my '95 into this '88 housing in order to use my EBC brakes.

I didn't know there were any differeces like this in these D30s...

 

[Mr. mud]

Just swap the knuckles and brakes, shaft length difference is minimal. What the problem is is that your Hub is different and so is the rotor. Different hat depths. keep your other shafts for spares though, they should all interchange unless one of your axles is equipped with that vacuum disco crap.

 

[CameronB]

OK, I'll disassemble and check things out. However, the axle flange surfaces ARE deeper 'inset' on the '88 shafts, as compared visibly to my '95 flange surfaces. Maybe I can get a pic up if necessary.

 

[stesul411]

The axle shafts and knuckles are basically the same from 84 through 96, the difference is the unit bearings and rotors. the 84-89 unit bearings are about 1/4" shorter than the 90+unit bearings. All you need to do is swap your 95's onto the 88 axle and your EBC's will work.

We run the early style 84-89 hubs and rotors on both XJ's (90 &93) without any problems. The early hubs have tapered roller bearings and can be rebuilt for about 40 bucks compared to 75.00+ for the later style with ball bearings that you just throw away when they go bad.

I have an set on the 90 right now that I drilled and tapped for a grease fitting, that works kind of like the old Dodge FPJ44 set up.

 

[CameronB]

Thanks,
Honestly, I've never taken apart a D30 yet, and didn't realize that this is a unit bearing issue. If I hadn't spent the money on the EBC brakes/rotors, I'd keep the old unit bearings so I could rebuild them as mentioned.

I'll be tearing into this project in a few days, and appreciate the info.