Those are JK Rubicon axles. Stronger than the TJ, however you would need to adapt them for your bracket setup. There are a lot of differences in these axle from the TJ's. They are wider, have bigger tubes, brackets, lockers, bolt pattern.
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I find it so funny that you can buy a new OEM D44 w/ locker JK axle for $1300 when an OEM TJ axle cost $1600+ If they had more gears available for the new JK axles, it wouldn't be a bad idea to swap new D44's under a TJ.
If you didn't want to buy the matching JK front youd have to promise yourself not to go into 4 wheel drive until you regear the front d30 or unless you already have 4.10's in the front... regarding wheel bolt patterns, youd have to get new wheels... and for the d30 front you could buy some spidertrax wheel spacers that convert from 5 on 4.5 to 5 on 5... that would also space out the front some to better match the wide rear... then youd buy TJ brackets and get them welded on... and add some way to activate the rear elec locker... setup for disc brakes
a few hidden expenses but still seems alot better than sticking with a d35
*and they'd be kinda like having mini-full width axles
Yah - expecially if your is a DD and you don't beat on it hard enough to need D60's or something. Once you get the axles welded up to fit a TJ, you can find complete sets of JK wheels and tires on craigslist for like $400