Who knows everything about Dana 30 parts?

I have a previously owned 90 XJ with a non disconnect Dana 30. I purchased new Yukon 4340 shafts and stock replacement unit bearings. The shafts are supposed to cover about 10 years worth of vehicles with 90 being right in the middle. This is the only option available from Yukon.

My problem is that there seem to be two different bearing and shaft combinations.

One design utilizes a seal in the back of the bearing assembly that seals against a slinger on the outer shaft. I refer to this as the large shaft/bearing combo. In the picture this is the bearing on the left.

The other design is a self contained seal that does not seal to a shaft and slinger. This style shaft is smaller in diameter so I refer to it as the small shaft/bearing combo. In the picture this is the bearing on the right.

http://i1200.photobucket.com/albums/bb332/JackSpeed01/Jeep/P1050026.jpg

My new Yukon shafts are the smaller diameter and therefore do not work with the large bearing and seal design. I imagine that running them together would allow mud and debris to enter past the seal and to ride directly against the sealed bearing thus reducing it's life substantially.

Does anybody know what the small shaft and bearing combo came from? I would check with my local parts stores but they don't carry ANYTHING. It took two weeks for my new bearings to get here.

Thanks

You may want to look at the randys ring and pinion site. They have pretty much every version of the D30 on the site.

I seem to recall that at some point the older hubs had replacable bearings but jeep changed to a different style that is not replacable unless you get the entire hub assembly.

I'm not sure when they made the change to the "new" style.

Thanks, I've spent quite a bit of time lately researching the bearings. They seem to have changes between 89 and 90. Although I can't seem to find anyone who says you need to match the year of the bearings to the year of the shafts.

The shafts are supposed to be good for both years plus many more before and after. My new bearings are the 89 and older style which is supposed to be stronger and longer lasting. If I worked for Yukon I would have built the shafts to properly match the application, that would be the larger design since it works with both bearing assemblies.

I'm not sure what the bearing on the right of my picture is from. My Jeep had one of each installed but the outer shafts were properly matched to the bearings. Since nobody stocks these bearings around here I can't look at any other years unless I buy them and have them shipped to me. Hopefully somebody knows the difference.

1. Take some measurements of the axles, the bearings, and the seals.

2. Call Yukon's tech support line and ask them WTF is up. If THEY don't know what is going on then you are totally screwed.

I emailed Yukon two weeks ago and they won't respond. I did not try calling yet. I gave all dimensions to the company that I purchased the shafts from and there only response was "You have the right shafts"

I have two stock shafts with different dimensions so it isn't only Yukon although their shafts do not fit the stock bearings for these years. There were two different ones but I'm not sure if it is from different models or years or what.

If you have a 90 XJ you should have the old style unit bearings my guess is theres 2 different styles for the "old" and "new" style bearings you may have an new bearing and old shaft or something to that degree