Like Duane said, unless somebody converted it (which would be a stupid thing to do) you DO NOT have auto hubs. It's more than likely your CAD is the problem and putting manual hubs on alone, will not fix it. You would also have to lock your CAD.
This is an explanation I typed a couple of weeks ago for somebody else and I finally got smart enough to copy it so I don't have to keep typing it. It was directed at somebody else's questions, but most of it will benifit you:
One good way to test if your CAD is locked when it shouldn't be is to: park it in 2wd, with engine running, crawl under and see if you can turn your front drive shaft with your hand. If you can, its not locking prematuely (at least not at that instant

). If you can't turn it, that means its engaged or partially engaged.
As far as your last question, lets back up a little bit and explain what CAD does:
CAD (central axle disconnect) is Dodges method of "shift-on-the-fly" 4wd engagement. On the long side of your front axle, there is actually a two-piece axle inside. Where you see the "bulge" with a vacuum motor on top, that is where the two-piece shaft engages/disengages (with a sliding collar) when it gets a vacuum signal from the t-case when you shift in/out of 4wd.
Your hubs are basically "full time" hubs, they are always engaged with the axle. When you are in 2wd, the axle is spinning, but it is disengaged (because the collar is not connecting the two shafts) from the inner shaft that goes into the diff.
On the passenger side, the axle shaft is one piece and does go into the diff, but it is only spinning the spider gear in there and the carrier/ring gear is not turning.
There are a couple of reasons to put manual hubs on. If your CAD is giving you trouble, you can lock it (see the FAQ on this process) and of course you need the manual hubs on so you're not turning your whole front drive train. This of course means you don't have true "shift-on-the-fly" anymore.
I put manual hubs on mine so I could have 2-low. I still have my CAD functioning normally and it has always been flawless for me. The reason that I stick with CAD is that I need 4wd daily to get to and from my house and it would get really annoying to have to get out and lock/unlock hubs all of the time. So, I can just leave my hubs locked in all of the time, and this is no different that the fulltime hubs that it came with, but now, I can get 2 low if I want, and I can just unlock them and save wear and tear (which is minimal) on the shafts, u-joints and spider gears.