Dana 30 Tech

[ocalajeeper]

I've got an 88XJ D30 disco. I'm about to get a 96+ D30 non disco. The 96+ doesn't have brakes. Can't I just put my rotors and calipers from the 88XJ on or is there more involved? thanks.

 

[CanMan]

The unit bearings are different, and the rotors have a different hat depth. Swap the whole knuckle over to keep it simple.

 

[ocalajeeper]

The unit bearings are different, and the rotors have a different hat depth. Swap the whole knuckle over to keep it simple.

I'm not going to need a press to swap the knuckle over will I?

 

[CanMan]

I'm not going to need a press to swap the knuckle over will I?

No, just a BFH.

 

[ocalajeeper]

No, just a BFH.

I just pulled the wheel to take a look to see what's involved. I'm going to need a 36mm for the axle nut correct?

 

[corbinafly]

yes.

 

[ocalajeeper]

thanks to canman and corbinafly for answering my questions, and thanks to crash for this original thread.

 

[RabidRabit]

I started out this thread with a pretty good idea of what I needed but now I'm confused as hell. I've got an 88 D30w/disco, I rebuilt it and added a Detroit Tru-trac and 4:10s as well as the posi-loc kit before sticking it back under my XJ. Snap, crackle, pop. So I bought some spicer 760 ujoints and now need to buy the proper stub axles to fit these.
I can use the axle stubs out of 95 and up XJ or TJ, is this right? I don't need to change the inner axle as well right? Just the stub axles. I dont' need to change any seals either right?

 

[WrenchMonkey]

No.

To upgrade to the larger joints, you need to swap both the inner and outer stubs to match.

Driver's side, you can use all from a late model XJ.

Passenger side, if you want to keep the disco, you'll need the inner shaft from a 95 YJ.

You can use late model XJ to eliminate the disco, but then you do need to change the seal.

Robert

 

[shanesaw]

I've got a 87 4.0 auto with an NP242 on 31" tires and am about to put an ARB in the D30. Crash's original writeup says to avoid going 30-spline because it will leave the R&P as the weak link, but that is with 35" tires. Would this also be the case with a smaller 31" tire? If I can go with a 30-spline carrier and axles, is there an XJ model that has stock 30-spline shafts? For cost reasons, I'd like to run some stock 30-splines (if they exist) out of a wrecking yard while I save for some good chromoly ones.

 

[RamAford]

Anyone have the measurements on stock upper and lower contol arms for mighty dana 30? Im building some control arms and dont have an axle to measure the width i need to make them. Ive found the length, just cant find how wide to make them.

 

[jeep pox]

I've got a 87 4.0 auto with an NP242 on 31" tires and am about to put an ARB in the D30. Crash's original writeup says to avoid going 30-spline because it will leave the R&P as the weak link, but that is with 35" tires. Would this also be the case with a smaller 31" tire? If I can go with a 30-spline carrier and axles, is there an XJ model that has stock 30-spline shafts? For cost reasons, I'd like to run some stock 30-splines (if they exist) out of a wrecking yard while I save for some good chromoly ones.

The Dana 30 came with 27 spline shafts

 

[jeep pox]

Anyone have the measurements on stock upper and lower contol arms for mighty dana 30? Im building some control arms and dont have an axle to measure the width i need to make them. Ive found the length, just cant find how wide to make them.

You question doesnt make sense. Only thing I can figure you mean is how wide the joint is. 2.625" (2 5/8")

 

[WrenchedXJ]

Crash, wonderful job on the write up. I do have this one question. I have a 89 rig(with the disco 30), then a 95 parts vehicle. My trans is bad and Im having to swap the aw4 and np231 from the 95 into my rig. While in doing this, I loose the vacuum switch on the t-case. To fix that issue, I was just going to space the fork to be locked in at all times. Is there a strength difference between having the fork locked vs. swapping in the non-disco from the 95? Trying to see if swapping the front axles is worth the trouble.

 

[kastein]

You can just swap the vac switch AFAIK.

If you don't want to do that (who wouldn't want the chance to eliminate some vacuum lines, right?) block it off.

I've seen people claim that the non-disco axle is stronger (no joints in the axle tube) and others claim that the disco axle is stronger (UCA bracket is cast/forged instead of wimpy pressed sheetmetal) but no real conclusive info on either side. I know that a few of the JeepSpeed guys have broken vac disco housings in half when hitting large bumps at speed, but I doubt most people will have that problem.

How many miles on each set of gears? Check the bearings, gears, and seals... if the 95 axle doesn't have as much pinion play and is in overall better shape I'd swap it and forget about it.

 

[89xj]

swap the shafts out of the 89(260 ujoint) so you get the larger ujoint(297). the ujoint is what you want to be stronger. but you would need an inner axle seal.

or just swap the axles.

 

[Darky]

I'd swap the 95 anyways. It's newer, you won't have to worry about the vac disconnect stuff, and most parts will be interchangeable, so if your 89's rotors are better, you can swap them over.

 

[Justpunchit]

anyone see the new outer stub shaft kit Alloy USA is making. 30 spline outers with bearings 500 bucks... something worthwhile?

 

[89xj]

I'd swap the 95 anyways. It's newer, you won't have to worry about the vac disconnect stuff, and most parts will be interchangeable, so if your 89's rotors are better, you can swap them over.

i dont think the rotors will work from the 89 onto the 95, unless you swap the knuxkle also.. the 89, which i also have, has a diferent hub design which uses a different unit bearing, brake calipers, rotor.

 

[WrenchMonkey]

<Edit> Nevermind, "89" types faster than I do! But yeah, what he said...

Robert