It's not about driving a truck with a front locker, it's about a front locker doing weird stuff to a truck with ADD. Yes it disconnects one side shafts but no that's not like having hubs, it's like having ONE hub, which as you can imagine, is gonna make the locker try to lock. If LSD it makes the truck pull to one side. It's not ideal. Now, a person could disable part of the add system so that the side shaft stays engaged all the time, which would make a locker or LSD fine in front, but it would put more strain and fuel consumption. As far as budget minded stuff goes OP, if you are NOT regearing, then consider buying an auto locker in the rear only and let the trac system handle the front. This will get you out of (or into) a lot of trouble. If you are regearing, then the cost increase to install a locker in front becomes much less, so you may just want to bite the bullet in that case. The regear question is multi layered and complex, will need to know the whole story before you can decide that.