D30 Rear Steer

I'm not planning anything but I had an idea, even though it has a lot of issues, that someone could put a D30 in the rear of their xj to get 4 wheel steering. Go with a low pinion D30 in the rear and a high pinion in the front to keep the best axle running in the best direction. You'd have to either get an offset transfer case for the rear drive shaft or maybe you could use dual cardan rear drive shaft with a SYE on a 231 to not get any vibes. Then you could either cut off the coil buckets and weld on some spring perches or you could be really ambitious and build a 4 link rear while you were at it.
This is purely hypothetical but most people have issues with a D35 yet most agree that for moderate wheelin on 31-33's you can't beat a D30 especially on ground clearance. So what do you think, this is purely for discussion, what else would you need to do? :chef:

You might want to consider a front D44 from a Rubicon. It's low pinion and will be stronger than D30 in the rear.

:laugh2:

The first thing I tought of is would there be room for the tires to turn inside the rear wheel wells? Even if you cut and rebuilt the wheel wells, the springs might get in the way. Sounds like a lot of work, esp if your staying with 31-33's. Something as cool as rear steering deserves big tires.

.02

Daryl

I don't know a lot about rear steering, but if you flip the axle around, wouldn't the knuckles be sitting at the wrong angle? If you have to cut and turn the knuckles, why not retube and put the pumpkin in the center or why not simply keep a rear axle and add the knuckles and necessary components instead?

How ya gonna steer it?

momentum

Eagle said:

How ya gonna steer it?

Click to expand...

with his butt

why do you think they call it "rear steer"?

D30's hold up better to 33's, not because they're stornger than the D35, but because they're in the front. Weight transfer puts more stress on the rear axle.

MaXJohnson said:

with his butt

why do you think they call it "rear steer"?

Click to expand...

HA!

MaXJohnson said:

with his butt

why do you think they call it "rear steer"?

Click to expand...

:laugh3:

Well If you wanted to go all out, not that I would ever put money into it, what about using full widths? Hack your fenders and lift it and with full width's front and rear they could handle some big tires....

For steering, why not a Rock Ram hydraulic system. Set it up for coils and it would be pretty much like a front end setup. If you convert to a fuel cell and get rid of the gas tank for more room you could put everything pretty much where ever you want....

Ya, A 30 in the rear would hold up for maybe one trip, there is so much more load on a rear axle than a front, the little bitty axles and joints would just explode, what about the off-set pumpkin, it pretty far offset for any drive shaft. :twak:

bgcntry72 said:

:laugh2:

Click to expand...

..

I say DO IT! I'm in the mood for a good laugh.

THREE, TWO, ................................................

one?

All you nay sayers have no imagination. I never said I was going to actually do it but if I had a lot of extra time and money you can bet I would do it just to show it could be done, not necessarily practical. I do agree that making room for steering it would require moving the leaf spring inboard and possibly widening the wheel well a bit.
I don't see why you couldn't run a hydraulic line tapped off the gear box (similar how many people do ram assist on the front) to run a cylinder on the rear axle. To control it I would have to imbed the lever in the driver seat cushion as suggested to actuate it with my rear end movement.
Using a Rubicon 44 front is a possibility but if everyone is so concerned with a D30 not being strong enought then why use a D44 that has the same size axle tubes, u-joints, and knuckles and a D30.
I think I will go change my blinker fluid now as you guys are no help. :laugh3:

GroversXJ said:

Go with a low pinion D30 in the rear and a high pinion in the front to keep the best axle running in the best direction.

Click to expand...

the wheels would turn the wrong way buddy...

GroversXJ said:

You'd have to either get an offset transfer case for the rear drive shaft or maybe you could use dual cardan rear drive shaft with a SYE on a 231 to not get any vibes.

Click to expand...

a dual cardan would hur you here - the way that you set up the "CV" driveshaft is so that the bottom u-joint has no angle. this side angle would give all 3 u-joints bad angle that would cause major vibes.
A single cardan would work best that way the angles of each of the TWO u-joints would cancle each other.

GroversXJ said:

Then you could either cut off the coil buckets and weld on some spring perches or you could be really ambitious and build a 4 link rear while you were at it.

Click to expand...

Leafs would be easier, but as someone said above - springs would be in the way - unless you inboarded them.

GroversXJ said:

This is purely hypothetical but most people have issues with a D35 yet most agree that for moderate wheelin on 31-33's you can't beat a D30 especially on ground clearance. So what do you think, this is purely for discussion, what else would you need to do? :chef:

Click to expand...

You would need a ring gear that would rotate the correct direction...
A d30 isnt worth all the time if you ask me. <joke>If it was - then i would just weld the knuckles straight and pop one in the back as a rear axle swap...
</joke>
you would also need some steering mechanisim for the rear of the rig and probably a lower geared gear box to turn all the tire. probably a steering colum going to the rear with like 12 u-joints in it...
Laddr bars for the rear so that the new steering collum doesnt get snaped during axle articulation.
some sort of lockout for street driving (if you ever did that) (just to the trail - obivously not a DD anymore)
much (numericaly) less backspacing on the wheels

and about $2000 for a new car once you realize that you fucked up your XJ...

the wheels would turn the wrong way buddy...

Click to expand...

This is incorrect. A front axle can be used in the rear, or a rear in the front with no changes in ring and pinion. The transfer case takes care of rotation issues. Think about it. Draw a diagram.

By trying to make this guy look bad, you've made yourself out to be the asshat.

Congratulations.

CRASH

GroversXJ said:

All you nay sayers have no imagination. I never said I was going to actually do it but if I had a lot of extra time and money you can bet I would do it just to show it could be done, not necessarily practical. I do agree that making room for steering it would require moving the leaf spring inboard and possibly widening the wheel well a bit.
I don't see why you couldn't run a hydraulic line tapped off the gear box (similar how many people do ram assist on the front) to run a cylinder on the rear axle. To control it I would have to imbed the lever in the driver seat cushion as suggested to actuate it with my rear end movement.
Using a Rubicon 44 front is a possibility but if everyone is so concerned with a D30 not being strong enought then why use a D44 that has the same size axle tubes, u-joints, and knuckles and a D30.
I think I will go change my blinker fluid now as you guys are no help. :laugh3:

Click to expand...

Grover, the real problem is U-joints. IN the rocks, we routinely and regularly see D-60 sized joints fail under load when used in a lightweight buggy under extreme conditions.

Yes, you are correct, full hydro would be the way to steer it. You could use a lockout pin to fix the axle for street use. I think your best bet would be to take a centered rear axle and add steering parts to it. Aftermarket D-60 parts would be a good place to start. Crane and Dedenbaer make excellent inner and outer knuckles. For 32's, you could probably get away with a regular spicer joint. Any larger and I would go to a CTM.

CRASH