in the rear a 44 from xj is you best bet, you need to do the spring perches , shock mounts , and drive shaft, need to be cutted arround an inch. the U joints are the same
over all an easy project, exactly the same width and bolt pattern, and bigger brakes. (I didt it so I know what im talking about)
in the front, if you whant to go with a stock low pinion dana 44, or a rubicon axle, I think is a waste of time and money if you have a Hi pinion dana 30.
dana 30 and dana 44 pinion neck diameter is the same (1.185")
a reverse cut ring and pinion (hi pinion) is about 20-30% stronger than a low pinion. putting it in the same ball park than a 44 gears.
(Hi pinion is cut for a front axle, a low pinion is a rear axle gear spinning in reverse, using the cosat part of the teeth to apply power instead of the drive part)
the axle shafts in a stock dana 44 (chevy, ford...) have a diameter of 1.088" at the neck down section.(weakest point) a dana 30 has a minor diameter of 1.145". YES THE AXLES IN A STOCK 44 ARE WEAKER.
a rubicon axle uses a low pinion same tube diameter and same outer axle than a dana 30. over all problably the same.
the only way to have a stronger 44 is to have a custom one with hi pinion, after market shafts.............. LOts Of money................
so build your hi pinion 30 with a good locker or lsd (true tracs use the similar internals in a dana 44 and a 30), axle shafts with bigger u joints (95 yj or tj, xj or chromoly),
and and axle truss if you like to jump. and call it good.
4.2 rocks....if you know how to build it.......
xj would be the easiest.
you can do any of these 44's in the rear with various required changes:
SJ centered 44 (waggy)
SJ model 20 (waggy)
passport or rodeo (plus cause it should have discs)
If you plan on having any type of real power I would scrap the dana 30. it is not stronger than a stock 44 especially the 3 pcs. garbage they put in the YJ. I went through 3 30's for bent housings at the shift motor. twisted knuckles and a slew of snapped shafts. I will tell you from experience that a d30 with 35's and 350sbc will not last long.
"We'll get out of this disaster in time for the next one"
"I'm done recomboobulating the energy-mo-tron"
88 YJ, 350/350 Chevy, Twin Stick Dana 300 with JB 32 spline rear output, 6.5" lift, Front Scout II Dana 44 w/Yukon 4340 shafts, trac loc, 4.27's, Warn Premium Hubs, flipped YJ Tie Rod, Ford F150 front calipers, Rear Scout II Dana 44 w/Alloy 4340 shafts, HD RPT retainer plates, 4.27's True trac, Steeltech Disc brakes, Cage upgrade, B&M Prostick Shifter, Custom Fabbed tire, gas, jack carrier, 3/8 angle rear bumper, clevis's all around, old & reliable rep8000 winch. Flood lights. loud stereo. 35x12.50 swampers and a bunch of other stuff