65 FJ40 - Doing it the Easy Way

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I decided to fully embrace the scope creep. What started with leaky wheel cylinders has turned into axle-swaps with dual-circuit brake hydraulics and front disks.

I bought someone's brakes/knuckles/axle shafts from their 40 project. I got an axle housing and knuckle kit from Valley Hybrids.

I just had to pull the diff out of the '65 so we could build the new axle.

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Ball & claw axle with Husky hubs.

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Normal snap-ring.

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The plastic center knob pushes these blocks to unlock or lock the axle to the hub.

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Normal big nut/locking washer/big nut arrangement.
 
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This wire keeps the bolts that hold the backing plate from coming loose.

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Disconnected the soft line and popped the backing plate off.

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That just left the spindle and axle shafts.

This side came apart really easy. All it took was some gentle encouragement with a deadblow.
 
I'm going to save the 9mm brake fittings but is there any use or market for any of this other stuff?

I don't imagine anyone would have an interest in ball and claw axle/knuckle parts or the old husky hubs.

I think I'll use the balls to make some custom truck nutz and the axle housing can be turned into a garage urinal or maybe a drill press stand.
 
I don't imagine anyone would have an interest in ball and claw axle/knuckle parts or the old husky hubs.
i would...just to have spares for the 61.
 
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The other side however, fought every step of the way.

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Eventually I had to remove the wheel cylinders from the backside and pound the hub off with a brass drift.

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Bolts wired together.

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The spindle wouldn't come out of the backing plate so that all came off in one go.
 
So why do all of this? Well, to stop the wheel cylinder leaks of course by installing disc brakes on a new axle.

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I just need to pull the third member from the '65, swap in these fine spline gears, and install it in the new housing.

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But the 65 had 8mm studs while the new axle housing had 10mm studs.

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A bit of precision machine work.

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Almost done.

I may have been better off buying a newer used third member. The viscous sludge that glopped out of the diff was alarming. And I could have avoided drilling it out.

The next challenge will be transporting it to my garage and bolting it up. Not sure yet how I will pull that off. Also special thanks to my friend at Valley Hybrids who is doing much of the build for me in exchange for wiring up his factory 80 elockers. That'll be another thread.

And I may have a line on a rear axle soon ...
 
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For the rear, as much as I dislike semi-float axles, I decided to be practical and use what I have. The easy way.

So, I've parked the 70 series FF project for now and decided to just convert the rear-end to fine-spline axle shafts, 10mm drum brakes, and add a Detroit locker.

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I've never seen drive shafts with rubber boots before.

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Double-nutted. Sure, why not.

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Why a Detroit locker? Leftover from another project. The donor.

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Third-member in a bucket and off to the diff shop. In the meantime I can get the brakes sorted.

For the rear brakes, I have some newer drum brakes with 10mm fittings. I don't know if the wheel cylinders are any good though. They look dry at least. Replace now or roll the dice and see if they leak?
 
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Alright I've got the diff back. Interestingly, what I thought was an open rear was actually an old Eaton LSD. I opted not to use that, in case it would be useful to someone with an early truck. It will be up for sale along with all my leftovers.

So I got another core from Valley Hybrids, and had the Detroit installed in it instead. Now to figure out if/how I am going to install it solo. I might get creative with ratchet straps, a floor jack, and some plywood.

The front axle is also built and ready to install. I need to figure out how to transfer that from Valley Hybrids to my garage. Probably by borrowing a hoist.

I've also done some digging on the engine. The engine ID, F0707HA, looks like a 275hp '66-68 L30? I haven't uncovered the casting # yet. It has a Quadrajet carb on an Edelbrock intake. I need to do a compression test and make a plan for this. I am kind of surprised the front ball and claw axles could handle that much power but maybe they weren't used much. I suspect I'll destroy some birfs :)
 
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So ... I forgot about the 8mm vs 10mm studs in the diff. As I now have a freshly set up diff with 10mm holes for the rear, and the front already converted over to 10mm, i'm going to replace the rear axle housing altogether. So much for using what I have, lol.

Enter this interesting option.

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From my reading, it looks like a '75-80ish full float rear, probably from an fj45/hj47? It's a bit fuzzy exactly what years and markets got this setup.

It has an 8 hole backing plate with two wheel cylinders per side, making it an "early" style. It has the heavier-duty 3" drums.

To finish it, I'd need a pair of drums. The ones with the cooling fins may have been stock. I think that is 43512-60020, and the front and rear interchange. After '80 they started using a different non-finned 3" front drum (43512-60030). I'm not sure if I could put that on this rear.

I also would replace or rebuild the wheel cylinders, as leaky cylinders are what got me started on this whole project. Not sure yet what I need. I guess I should pull one off and measure it.

I have a spare set of 70 series axle shafts that I believe will work here.

I have one spare rear hub and can track down another.

Or maybe the rear should be disk brakes too ...
 
Yes, that is a 75-80 axle from a 45.
Make sure you measure the cylinder bores before ordering rebuild kits/replacements as they are usually bigger then regular 40/55 stuff. The shoes are wider as well.
70 series axle shafts will go right in so you are good to go there.
 
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