Building FJ40/60 axles to custom widths & with Disc full float.

[abosely]

Ok I started working on this a good while ago and started a thread but it’s been so long, thought I’d start fresh now that I’m moving forward.

I’ll brake it into two posts, one about the background & second about the process. Still probably going to be a bit long threads & have quite a few pics.

I’ve been a LC guy long time, and wanted to build an FJ50. Ended up on Big Island HI and a FJ40 to build wasn’t go to happen.

But I did stumble into a 69’ Series IIA SWB Land Rover!
To keep this on point and short as possible. It needed a new chassis, axles running gear etc, basically I got a body with a title! Lol

I had got a set of 87’ FJ60 axles & diffs. So decided to modify them for the SIIA, incorporating 4 wheel disc brakes and full float rear axle.

The reason I’m posting this on Mud even though I’m building a LR, is this modification will work for building FJ60/40 axles to different widths, pumpkin/pinion locations (if wanted) and converting the rear axles to Disc brake and Full Float.

This actually turned out to be pretty straight forward and less expensive than buying a new custom housing, plus for me keeping the basic stock housings look compared to a built up housing was important.
Not knocking built up housings at all.

Stock SIIA have a WMS to WMS of 55” front and rear.
I’m having rear WMS to WMS of 57-½” and front of 59” WMS to WMS.

They also need the pinion moved further to the right side to line up in stock position.

Ok, so there’s a bit of background of how & why I ended up doing this and that this aspect of my LR build directly relates to Land Cruisers.

Cheers, Allen

 

[abosely]

I’m just going to show the rear axle build first and if anyone is interested, I’ll write up the front then also.

 

[abosely]

 

[abosely]

Ok didn’t mean to post them without a caption! :-/

Well the flange ends of zan FJ60 rear axle. The FJ40 is basically the same but shaped a little differently, but you remove them the same & they end up the same after flange is removed.

To remove the flanges use an angle grinder & cutoff blade to cut through the welds on both sides of the flanges.
I found using a propane torch helped out. Just use a snog ol hammer & pound around the ears of flange & it will eventually slide off. May have to check & see that the weld is cut all the way through. If you go a bit to deep it’s wont be a problem, but better to avoid it as much as possible.

That gives a machined surface on each end of housing that is uniform and aligned with each other on both the outside and inside of tube to work from.

 

[abosely]

Then chucked it in an old 1920s lathe and indexed off the machined inside surfaces to extend the factory machined
Outer sections inboard as needed, so when trimming the housing to the length on each side a bit, there was enough machined length to fit the sleeves over.

Which results in this.

I didn’t bother to even the length of the machined section to match on each side.

This is where I left off for good while, then yesterday arrived at the point that I was ready to fit up the sleeves for the ends.

 

[abosely]

I started with a piece of 3” Schedule 40 pipe and cut it to length using my trusty angle grinder & cutoff blade.
It had a slightly loose fit over the finished ends, as anticipated.

I cut a small section, a bit less than ¼” wide to be able to fit them tight to the ends.

I did this using my high tech Island technology to press it down tight and evenly around the tube, and to hold it in place for welding.

I used heavy tacks all around it & in the seam.

Then welded them up. I didn’t want to have a sharp step down from the thicker sleeves to the thinner tube.

So I welded them all around, came back and ground the welds a bit to clean and smooth them up and made multiple passes around it to build up a tapered fillet transition.

The sleeves add back material that was removed from the tubes on the inside the factory machined (I think it’s so s housing can be used for the front or rear possibly, I don’t see any use or need for it on a rear housing) it comes out right to 3.5” so a pair of Ruff Stuff Disc/FF flanges fit right on and are easy to line up.

More about lining up the flanges for final fitting to come.

The little nun of weld bead is there on one side to tighten the fit slightly for initial alignment.

I left the ends slightly long and ground them to final length. But when doing so removed good bit of the weld of the ends of the tubes and sleeves.
Not a problem because when the flange is welded in place all three, the tube, the sleeve and the flange will be welded together on that face.

So the welds aren’t as boogery as the look. Lol

Next, how to seal the RCV FF axles.

Cheers, Allen

 

[abosely]

Well a great way to deal rear FF axles with a front spindle & hub was came up by J Mack!

To me part of its brilliants is in its simplicity, which I believe will be a big asset to it long term durability.

His solution was to machine a pocket on the inside of the front spindle and fit s Marlin Crawler Eco Seal!
It has the ability to handle a bit of miss alignment and seals great.

So now we just run the inner rear axle wet and the outer spindle & hub with grease like it is on the front!

This is s picture of J Mack’s chromoly spindle with the eco seal in place.

A picture of one of my spindles with the pocket machined out,

And one of mine with the Eco Seal set in place.

Just a close up of spindle & Eco Seal.

Will use FJ60 calipers and vented rotors
and RCV chromoly custom length axles and have them press fit the drive flanges on shafts for me.

The only other minor thing is to have RCV machine a smooth section the appropriate diameter where the Eco Seal rides on the shaft.

I forget the range of WMS to WMS that can be built by using either FJ40 housing cut down some or a FJ60 housing and extending the tubes with sleeves.
But they could be made substantially narrower than a FJ40 or substantially wider than a FJ60 and get rear discs using off the shelf FJ60 calipers & rotors and FF axle with any cut to length FJ after market axles.

Trying to use Ruff Stuff Disc/FF flanges on a FJ axle is somewhat difficult unless the housing tube are machined for fit and alignment. They are really more intended to mount on DOM tubes housings. But this solves that little issue.

At the same time the pumpkin can be made centered or position changed.

With minimal work and expense.

If anyone would like to see the front housing I’ll make a thread about it.
The front is slightly more work, but not much.

I have a Face Book page 69’ Series IIA Build that has more details on the axle housing mods,

Cheers, Allen

 

[SuperDuperCruizer]

Nice work... I was thinking about doing something similar to a 40-series rear axle. What is the length of your lathe’s bed? I have access to a metal lathe but wanted to make sure it was large enough to handle the job.

 

[abosely]

Nice work... I was thinking about doing something similar to a 40-series rear axle. What is the length of your lathe’s bed? I have access to a metal lathe but wanted to make sure it was large enough to handle the job.

It wasn’t my lathe, but I think it was about a 7’ bed.
Not really knowledgeable about lathes & machining.
But it took less than an hour total for the rear housing.

Cheers, Allen

 

[GLTHFJ60]

Awesome job.

 

[Ryan Towry]

nice work. I have been building a similar set of axles using a FJ60 front widened on both sides and a rear FF FJZ80 widened on the short side to both be roughly 67-1/2" WMS to WMS.

I would definitely try and find an alignment jig to help make sure the axle is strait upon rewilding. My rear was really close but the front housing took a decent amount of massaging.

 

[abosely]

nice work. I have been building a similar set of axles using a FJ60 front widened on both sides and a rear FF FJZ80 widened on the short side to both be roughly 67-1/2" WMS to WMS.

I would definitely try and find an alignment jig to help make sure the axle is strait upon rewilding. My rear was really close but the front housing took a decent amount of massaging.

Yes, I’m going to definitely get a set of alignment pucks and bar to make sure they are straight.

As much as I hate to fork out the money for it. Just not worth trying to save a few bucks and end up with axles they aren’t dead nuts straight.

Cheers, Allen

 

[Ryan Towry]

Yes, I’m going to definitely get a set of alignment pucks and bar to make sure they are straight.

As much as I hate to fork out the money for it. Just not worth trying to save a few bucks and end up with axles they aren’t dead nuts straight.

Cheers, Allen

that is exactly how I felt, not to include the time spent putting them all together. I ended up lucking out and found a friend that had already built pucks and a bar for a similar axle build.

don't want to clutter your thread but if you want to see what I was building here is the thread with most of my info:
T100 Family Wheeler. AKA the Mutant Turtle - Page 2

 

[gpfj40]

Good desicriptions here, I’ve been thinking along the similar lines in recent months.

I’d certainly follow along on your front axle mods.