Here is what they posted:
"The knuckles, tubes, and suspension brackets are just adaptation pieces to attach the axle to the vehicle. The part that makes it a 44 or a 30 or whatever is the parts that carry torque. The TJ Rubicon has the larger model 44 gear set and larger splined shafts and stonger U-joints at the wheel ends. The JK Rubicon got similar imporvments with the Model 44 (this time we got the high pinion) and 30 spline shafts and stronger U-joints (this time they got bigger and not just a material change)."
It says 30 splines while I have heard 32 splines, so I don't know.