What I'm working on now: Axle Swap and Shock Shifters

[lupinsea]

Just a quick post about what I'm working on now. . .

The axle swap is well underway and in the middle of that I've decided to do a shock shifter modifiction as well.

Some of you might know I picked up the stronger rear D44 axle out of the Jeep Wrangler Rubicon edition to replace my current rear axle. Along with a number of goodies it has the factory air locker in it which I'm looking forward to. So it is a strength and traction improvement.

All told the project is encompassing these major phases:

Axle Swap
This is the basic mechanics of getting the new axle installed and mechanically functional. Normally, the new axle is a straight bolt-in swap. But I needed to re-set the pinion angle as well as add lower shock mounts) and I'll be swapping out the pinion yoke for a different type.

Electrical Installation
The axle locker is air actuated and requires an air pump. This requires electricity and I'll be tapping into the Jeep's Power Distribution Center and opening up the dash to install the necessary relays, switches, and wiring harness.

Pump Mounting
The pump needs to be bolted under the hood, hooked up to electricity, and have the air hoses routed to the axle and to the firewall / air filter.

Shock Shifter
This is the biggest PITA of the project. Trying to re-design the suspension system. I'm basing it off of an existing aftermarket kit but otherwise having to reverse engineer it based on looking at internet photos. Normally it's a $130 kit but I can fab it up out of some scrap steel I have kicking about my garage. The tricky part is accounting for the movement of the axle. As the Jeep suspension cycles the axle moves left to right, up and down, and slightly forward or backwards, not to mention it also rotates slightly.

Step one: removal of the old axle from under the Jeep.




The new axle on jack stand so I could weld on
some mini-skids and box in the lower control
arm brackets. It helps to strengthen them as
well as provide a base mount for the shock shifters.




New axle under the Jeep. The suspension links
are loosely fitted and the springs, shocks, and
swaybar left out so I can flex the axle throughout
it's range of movement to check clearance for
the shock shifter mod.




I wanted to re-use my old OEM forged steel track
bar instead of the adjustable unit I was using.
This required modifying the factory track bar
mount since the rotation of the axle housing to
accommodate a different type of driveshaft got things
out of alignment. Only half of the bracket is fabbed
up right now. I'll make the other half once the axle
is pulled out from under the Jeep again for
final welding.




With the axle "located" with all the suspension links
and the housing re-set at ride height it was time
to work on the shock shifters. Here the mounting
tabs are bolted into place on the rear cross member.
To this I'll weld on various bits of steel for the upper
shock mounts.




A cardboard template and the piece of steel
I'm cutting for the upper shock bracket.




Compressing the axle to the bump stop to
check for shock clearances.

[lupinsea]

Measuring compressed and extended shock
lengths so that the shocks are not what stops
the suspension up travel. I wired the shocks
to stay at a fully compressed length and at
the normal ride height length to make it
easier to check fitment and position various
bracket pieces.




Adding the shock shifter lower mounting plate.
It's cut very large so I can make sure the lower
mounting tabs land on it. I'll trim it down to size
later. The white line represents where the
aftermarket kit aligned the lower shock end in
relation to the control arm bracket. Seemed like
a good place to put mine, too. Note marks of
where the shock bushing sleeve aligns at various
suspension points.




With a better idea of where the lower shock
ends up, I tack welded in the necessary bits
o' steel to lock in the geometry of the upper
shock mount.




This the the upper bracket when removed from
the Jeep. It looks nasty and crude right now
but once it's fully welded and a few bits
ground down it'll be much better.




Fabbing the lower shock mounts.




Getting these aligned was easy. . . bolt them
to the shock, move shock into position, tack
weld, done. As you can see, the plate they
are welded to is rather huge. It'll get trimmed
back as much as possible and the mounting
tabs themselves will be rounded over.

This is as far as I've gotten as of last night. I started at the beginning of June but have had many nights where I couldn't work on the project. With the first shock shifter largely "in" I feel like I've turned a major milestone on this project. Still lots of work to do. But I think I can get the Jeep ready to roll for a camping trip at the beginning of July with my son.

[kognito]

I see you have a floor jack.

If you find yourself needing another, let me know. I won't be using mine for a while

[bren]

That's cool and all, but seems like a lot of time and effort to save $130.

[lupinsea]

Originally Posted by bren

That's cool and all, but seems like a lot of time and effort to save $130.

Yes, this was my conclusion a few days ago. . . . but I have more time in the evenings than I do the $130 to drop on the Jeep.

Adding the extra $130 on top of the $1200+ spent on the regear, the $400 spend on fixing other worn components on the front axle, and the $800-900 for tires that the Jeep also needs would not go over well from the finance department.

[lupinsea]

Originally Posted by kognito

I see you have a floor jack.

If you find yourself needing another, let me know. I won't be using mine for a while

Thanks! But I think I'm good with the one floor jack for now.

[lupinsea]

Pulled the axle out from under the Jeep again so I could better finish the welds. They look a bit blobby but they'll hold.

Man, I went through a lot of angle grinder cutting disks, 4, in the last day and a half. For some reasons these discs kept binding up when cutting through the plate steel. And at ~12,000 rpm when they do that they crack or chip and then start disintegrating rapidly after that. So, I picked up another disk this morning. That and more welding wire. Ran out of the welding wire last night after HD had closed so I couldn't do much additional work.

[lip277]

Ummm... I may call on you for a favor.

With what I see you able to do - should take 10 minutes.. haha

[Pinecone]

Dude, those welds look awful.

[lupinsea]

Thanks. . . yes they do.

Made more progress this weekend....

Finished welding all the brackets on the
axle, including the trackbar bracket. Got
the TB bracket braced in with an extra
piece of plate steel.




Detail shot of the trackbar bracket with
it's curved brace plate.




The axle all painted and ready to re-install.




Starting work on the wiring harness. Here
I'm soldering extensions onto the leads coming
out of the relay module block. Doing it per the
Factory Service Manual: Add metal crimp to
the splice, solder, then heat shrink.




Spent a good chunk on Sunday building
the wiring harness. This is laid out how
it wraps around the engine compartment
then goes back along the frame rail to
the rear axle.




Got all the factory connectors that I could incorporated
into the harness and soldered up. But in a few locations
I needed to resort to some slimmer connectors
on single wire strands.




Taking apart the dash to add the switch
gear to the factory dash bezels as well as
plan the routing for the wiring harness.




This is as far as I made it last night: most of the interior dash
harness is done but for the terminal connectors at the
firewall/ground and wrapping it up in electrical tape.




Safety switch installed in the speaker
bezel (this will "arm" the system). And
the main dash switch with indicator light.
The last two fit the accessory switch
bezel on the center stack.




Dash switch and indicator light installed
into the accessory bezel.