JKU: RPM's Custom Hex Housing Diff Build

[rpm]

I Thought it was time for a build thread...



I bought this JK a while ago. It was previously Bill from DBOR's old Jeep, so it had all the good stuff already installed, except for the polished turd Dana 30 front diff that had been sleeved, gusseted, etc, to strengthen it up. But it was never going to be upto the job.

So after wheeling the jeep a few times, it became obvious that the front diff needed a serious upgrade from the tiny Dana 30 to something that could handle big tyres and the abuse that comes with wheeling the harder tracks. I did a bit of research on the net, made a few phone calls and ended up getting onto a local engineering workshop called Aikman Engineering, or AE Performance as they’re otherwise known as.

AE generally specialise in high horse power drag cars and street machines. They know how to build a strong diff capable of handling crazy power. After having a chat with Brian the owner, he was keen to take on the project of totally new from the ground up front and rear hybrid Nissan Patrol / Dana 60 Hex Housing diffs. Sure, it would of been easier to order a set of Dana 60’s from the states and just bolt them in, but the whole custom hex housing idea really appealed to me. I wanted something different and I liked the idea that I was giving work to a local workshop that was only 2km from my house.

It was always the intent to have my car engineered for all the mods including 37’s. After consulting with an engineer about the proposed mods, he was happy to sign off on the project, provided it passed all the necessary tests and requirements involved. The Jeep isn’t engineered yet, but I’m hoping it will be in the future once my bank balance recovers... haha...

The current front setup consists of H233 Nissan Patrol front diff centre with 4.88 diff gears and ARB air-locker, 35 spline front axles, Dana 60 C’s and knuckles, custom machined hubs, custom Wilwood grooved and slotted rotors wired to custom centre.

The rear setup is a H260 Nissan Patrol diff with 4.88 diff gears, ARB air-locker, 40 spline full float axles and custom machined rear rotors to suit 6 lug Nissan patrol stud pattern.

I’ve done a couple of shakedown trips as well as a trip up to Albury for a mates wedding and it all seems to be holding up together nicely. The ABS, ESC and cruise control all work perfectly aswell which is a bonus...



More pics and vids to follow

[rpm]

So it starts with designing up the diffs on CAD. This enabled everything to be designed properly with correct clearances so nothing fouled and it worked properly.





This is the rear Hex centre all folded up and welded.



Rear full float hubs being machined up.

[chris0375]

Almost like I stumbled upon pirate 4x4. Great to see some custom work done in Australia.

Sent from my C5503 using Tapatalk

[rpm]

Next was the rear diff welding and assembly. Aikmans have made jigs, so if anyone else wants a set of diffs made up it can be easily replicated.


The tubes and housing are 9mm thick.


Lower rear spring and panard mount.

Lower control arm mounts.

Rear spindles.

Rear H260 diff mounted to the hex housing

Upper control arm mounts

The rear all painted up.




And finally it got installed in the Jeep.



40 Spline rear axles


The rear axles after treatment.

Rear full float hubs. You can undo the centre nut and remove the axle with the wheel still on if you need to.

Isotropic treated crownwheel and pinion. Extra strength and less friction...


So the rear was basically all done. We lowered it off the hoist to see what it looked like with it’s wheels on. I was pretty happy with the result.

[Dan D]

Hey mate

AE do great work have seen there work on race cars before.

Did you gostandard JK diff widths or have you's gone wider ??

Reason I ask is I am hoping to do the same in near future.

Cheers Dan

[rpm]

Hey Dan,
Yeah it was a shame that they painted the diffs. It would of been nice to just clear coat everything to show off the workmanship.

I just went with standard width. I already struggle to fit in some ruts because the JK is so wide. Plus the engineer had strict requirements when it came to the overall width.

Just so you know, if you were thinking of going with AE diffs, they made pretty much 2 sets of everything and have all the jigs ready to go, so in theory it should be a pretty quick process.

[rpm]

Now the rear was basically finished it was onto the front.



Axle tubes and C ends.



Front Hubs



Willwood grooved and slotted front rotors. The rotor is bolted and wired to the centre section.




The front housing coming together.