hubs don't make it posi, you must have a posi unti it in to keep them both locked in. In most rear ends and front as mentioned both get power and turn but as soon as one gets off the ground ALL power it transfered to that wheel unless you have posi or a locker, then both wheels keep equal power.
The posi or lockers need to unlock and let one freespin when turning, this would be why some say stay under 40 mph when turning and such. How much of it you can beleive not sure. New cars come all wheel drive, all the time and you have to run over 40 mph in them.
alot of times the t-case turns everything, but supposed to when you have it in 2wd it disengages the front driveshaft so it won't tunr, maybe free float or something, saving gas and not turning anything.
Ok same thing for hubs, you lock the stick and case in 4wd and that makes the t-case turn the front, turn the DS and turn the ring and pinion gears which turn the axles.
Then you get to the hubs, they are unlocked, the axles don't turn them. So power gets to them but not to the wheel via the hub. You lock it in and viola power to the wheels to turn.
each axle has a spider gear, on the sides, positrac or lockers basically locks them into the axles, making them turn. So to speak, that's not exact but close to give you an idea of what happens. I aint sure how to better explain the posi crap. Most just cause the guts in the middle spider gears or what not to lock over and stay pressed into the axle making the ring and pinions turn both, not just one. When turning one backs off to let that side free float, follow or spin faster whichever you want to call it.
Lockers from what I understand do just that, lock both in all the time. posi's let the one free wheel so you can turn easy.
