In due time i want to install a locker. Preferably a manually selectable one, Ox locker or vaccuum locker, since i want to keep it 6 volts so compressor powered or e-locker is not an option.

Actually i found out any selectable locker is not an option only the Lockrite is available for the 10 or 19 spline D44. It's kinda weird no one has made one since i think there is a market for one since not everyone is charmed by the behavior of the lockrite on road on a lightweight short wheelbase Jeep.

So i am looking for options other then an axle swap, one thing that came to mind which i cannot really find an answer to is this (which probably means it wont work lol) :

Do the differential parts of later d44's fit the CJ3a diff housing? Carrier, gears, ring and pinion? I regularly see complete assemblies offered by people who went from stock gearing to lower gearing in the d44. 5.38 as in the CJ3a should not be a problem secondhand or new. If offcourse it fits.

Now your thinking, yeah nice but the splines Bubba, 10 vs 30. Well yes, but axleshafts can be custom made, cost set aside, it should not be a problem to have a axleshaft made with 10 splines on the wheelside and 30 on the inner diff side. If later model d44 parts fit, you can have any locker you want by replacing rack, pinion and carrier and use 30-10 spline shafts?

With the power of the flathead you do not have to worry that much if the splines are rolled or machined, using modern stronger steel for the shafts should be more then enough to ensure they wont break with the stock engine.

So how viable is the above idea apart from cost? Do later model parts fit the CJ3a D44?

Only option is to use a flanged offset D44 from a 1969-71 CJ.Those were the only years this axle was used. They are the correct spline count for an OX locker and are offset so you can still use the D18. The gears swap between this axle and the older 44, but that is about it.

The painted axles will be going in my jeep soon. Both have OX air lockers. The front is a D30 narrow trac and the rear is the flanged offset D44.

It's just a matter of getting used to it... I know your Willys will behave differently since I drove a Bronco with rear Lockrite locker for 8 straight years... it pulls and pushes in turns and wheel spin on wet surfaces is annoying too and that "bum" when it clicks on... matter of preference I guess.

Keep in mind that the Herm full floater kits are only 27 spline on the outer end so they are weaker on the outside than on the inside.

As far as I know the D44 covers all have the same bolt pattern.