The simple answer:
You did not specify if you have a D30 or a D44. If it is a D30 - don't throw another dime into it as no matter how strong you make the tubes and stuff, the gears are just too tiny for these big heavy beasts on large tires. If its a D44, read on.
As you probably have figured out, Rubicon 44s are not really D44s (this goes for TJs and JKs). The center section and gears are true D44, but the axle tubes, Cs, ball joints, and outers are Dana 30 parts. Also, stock JK front axle shafts suck bad and are the weak link in the system due to the stupid half-clip design used for the caps/ears.
It you plan to get loco and wheel with BIG meats, don't waste a penny on your 44. B-rad did everything you could possibly do to his; gussets, sleeves, beefier mounts, RCV shafts, etc. The best that money could buy to have something that still isn't a D60. I leaned from his mistake.
Now, if you plan to wheel like a normal human being (don't go apeshit) and keep the tires 37" or smaller, you can build a pretty decent JK 44 with commercially available parts on the cheap;
Poly Sleeves = $100
http://www.polyperformance.com/shop/Syn ... 20274.htmlPoly Gussets = $65
http://www.polyperformance.com/shop/Syn ... 21273.htmlPoly ball Joints = $125
http://www.polyperformance.com/shop/Syn ... 26182.htmlNitro Chrome Moly axle shafts with 1350 U-joints = $700
http://www.jkowners.com/forum/showthread.php?p=398980So you can build a pretty awesome JK D44 for under $1000 in parts.