Annnnnnd, a locker isn't going to get you through muddy ruts where grip is limited, and ground clearence important.
There are two ways of going about setting up your truck:
Go for lockers and big tyre's etc etc as you should alway's go with a second vehicle, so the likely hood walking 6 hours for help is minimal anyway,
or,
Make sure your vehicle is totaly self recoverable, especially if you go alone. No amount of diff locks, suspension lifts, 40' tyre's, boost gauge's, fluffy dice and neon's are going to get you out of the mud if your bellied high and dry, or sunk up to the window's in pea gravel. A winch will though....................
You can get your self out of a lot of places by using your winch inconjuction with burying your spare wheel with your spade, and hooking the winchg cable up to the highlift jack behind the burried wheel.
I reckon you should get:
Spade
Highlift
winch
A locker will get you into more trouble if your alone, but after your self recoverable, then get the locker
