Like said above, it would make sense to keep the 30 as long as its in good shape. Upgrade to a 760x ujoint and good shafts and you'll be just as strong as a 44. The weak link common amongst 1/4-3/4 ton axles is the ujoint (which are all the same size). The only benifit to a 44 is you can go with a lower r&p. On the other hand, assuming you have the 32rh non overdrive trans, the lowest I'd go even with 37s is 4.88 for any decent highway speeds. A 44 also has locking hubs which do come in handy. Honestly for what you'd have in a 44 you can swap in a 60 for a little more. If I had used that common sense years ago when I did the so called "1/2 ton upgrade" I'd saved myself an ungodly amount of money.