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D30 axle/steering/brake upgrade ?

PacificEd

NAXJA Member
NAXJA Member
Location
Middle Tennessee
I've been thinking about upgrading the front D30 in our Grand Cherokee. When I had it aligned, they told be the stock ZJ D30 had a bit of a bend to it. I also found a Ford 8.8 rear diff with an open case with 4.10 gears. So I'm planning to swap in it eventually.

I've been eyeing JK wheels and really like the stock steel, Rubicon, and some early JK aluminum wheels. So keep this in mind as I'd need 5-4.5 to 5-5 wheel adapters.

So this got me to thinking why not throw in a WJ front axle? It would get me the 5-5 bolt circle, crossover steering, and bigger brakes. The downside is that it is a low pinion.

Then I started thinking of going with a XJ D30 to get the high pinion. This would require swapping in all the WJ outer steering, knuckles, etc. The advantage would be I could now use the WJ unit bearings and the rotors which would have the 5-5 bolt pattern to work with the wheels I've been looking at and have the high pinion for strength. My question would be on this, do I need to use the unit bearing spacers? I think since I'm using everything WJ out, the spacer problem isn't necessary since I'm not mixing XJ/WJ outer parts.

What would you do for the axle? This ZJ is a DD/mild trail (gravel roads and dirt trails) rig and will probably end up running a 31/1050R15 tire with 4.10 gears. I'm thinking of just going with the WJ front as they are plentiful and would just swap in, correct? Low pinion wouldn't be a big deal with only 31's.
 
I asked this question before as well as I’m running JK take offs. If I remember correctly it has more to do with the 30’s stub shaft length needing the xj bearing and spacer, and the wj bearing not getting there.

On top of that I’ve got an 8.8 in the rear as well and you’d still need to convert it. Since they’re a bit narrower and the jk wheels tuck in quite a bit you really need that adapter’s width on the rear.

I determined it would just be easier to do the swap as normally done and run the adapters
 
I did some checking and see that all the WJ front axle shafts have the CV joints rather than a U-joint. By what you mentioned above, the stub shaft of the XJ/ZJ shaft must remain in phase to keep from binding.

I've also thought about just using the 5-4.5 pattern and doing the WJ knuckles for the big brakes and steering since, like you mentioned, the rear has to be adapted also.
 
So I believe the issue is two fold. One, CV instead of u joints as you mentioned the other and low pinion. Doing a WJ swap on a D30 is an awesome upgrade, pricey but worth it. Personally, I'd go with stock WJ as the first choice simply due to ease, but if you're up for it can't go wrong with a WJ swapped D30.
 
I tried the WJ brake/knuckle swap using CV instead of u-joint axles. Do not use a CV axle, it will bind just enough to where it will not track straight. It was a very frustrating and scary at the higher speeds. This is even with the spacer welded on.
 
The thought was to maybe swap in the entire WJ front axle since there probably isn't a lot of difference in price buying the entire axle vs just the brakes and calipers. The only downside would be giving up the u-joint axles for the CV's.
 
I think the wj dana 30 has slightly different location and perch size for the springs, different location for control arm bracket. I know the track bar bracket is over axle instead of under. It is also like 3" wider than the xj dana 30

When I tried doing the swap, i basically bought a WJ axle, swapped all over that I needed. I was trying to figure a way to use the LS in the wj axle, but the clutch packs are off to one side. Very different.
 
I wish I was smarter than this, eh, Ill just up my post count.

Anyway, since I cant edit my post..


If you are going to use the WJ axle vs XJ, then you should be able to use the CV axles and not the Ujoint axle shafts.
 
You can get u-joint WJ stubs and use them with the XJ inner and this should all bolt together and work.

The bigger problem overall here is that the JK wheels you originally wanted will be too deep of a backspacing. WJ/JK axles are much wider than XJ axles,

Really I think what you want here is a set of JK axles, or the 'normal' xj/wj swap and wheel spacers back to 5x5, which sounds stupid, but is what works out best on paper.
 
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