Dana 30 Disc swap are all 30's the same

My search didn't provide me with the information I am looking for. Can anyone help me out, I want to swap out my drum brakes on a 75 CJ dana 30 with disc's. I can buy a complete dana 30 out of a (1992 to 1997/ YJ fairly cheap. Are all the Dana 30 brake parts interchangeable?

 

No, they are not

For one thing.. they have a lug nut pattern of 5 on 4.5"

 

YJ dana 30s are 5 on 4.5 wheel pattern. Theres enough guys around swaping full size axles and one tons you should be able to find what you need. Make sure you notice the drum and disc spindles use a different inner wheel bearing.

John

 

1986 and back can be made to fit with less issues.
cjvet

 

I knew the bolt pattern was different, will the caliper brackets and calipers fit? I was hoping they would and then buying rotors and use my existing hubs. Is this comb feasible? Sorry for the limited information on my original post.

Thanks

 

When I did the swap on my 72 I got a complete front axle from a 78 CJ7 that a friend was parting out. I thought that all I needed was the spindles, spindle mounting studs, caliper mounts, calipers, dust shields, rotors and hubs, but when I started to assemble the brakes I found that the calipers would not work with the drum brake steering knuckles and the outer stub axles were different however I have the early Kelsey Hays brakes (Ford style) and I think the calipers are bigger and I know that the caliper mounts are different and the rotors are thicker than the later 79-86CJ brake systems.

 

When I swapped the '73 CJ5 axles into my '83 CJ5 I swapped 11" disc brake assemblies off from a '79 Dana 30. I used the knuckles and everything attached to them from the '79 . The '79 had the 6 bolt caliper brackets and I have 2 '78 Dana 30's that have the 11" brakes with the 2 bolt caliper brackets.

 

Another back when I did my swap (getting disk brakes on my 75 CJ5): I got a dana 30 from a 1977 CJ7 from a friend. I took the spindles from my axle (75 with drums) and had the backs machined down so that they were identical to the 77 spindles, pressed the studs through the rotors onto the 75 spindles and used the 77 knuckles and calipers. I did this to keep my 6 bolt warn hubs from the 75 axle, the 77 had these half plastic 5 bolt things, and I got to keep my 75 axle.

 

I recall someone here posting that the XJ/YJ/TJ 30 has a different caliper mounting or different knuckle or something major different from the CJ. Search and you might find the post, or maybe someone will respond with specifics.

Certainly you can use the parts from any CJ 30 though.

 

Unfortunately not and you can't swap the knuckles out as they don't interchange. The spacing between the ball joints is different, and the YJ/XJ axles use a unitized wheel bearing/hub assembly that is non serviceable. Forget about using the stuff from that axle, it just won't work.

 

Thanks to all for the great help and advice. You saved me both time and money.

 

Yep, when I did my 74CJ, I purchased what I thought was everything I needed off a 77CJ on Ebay. Turned out that my knuckles need to be ground down to match the contours of the disc brake knuckle. I also had the hubs that were not machined on the back. It ended up that it was cheaper for me to buy new hubs from 4Wheel Parts than have the old ones machined. Later I bought a set on 77CJ knuckles that I was going to swap in, but never did.
So..., If anyone needs a set of 77CJ steering knuckles or a set of 74CJ hubs, I have them.

 

will the disc's off an 81 cj swap onto a 73 easily? i'm replacing my 81 cj 7 with a 73 cj5. i too thought d30 to d30 would be a direct bolt on since both are cj's.