Dan:
the v8 4runner's come standard with fulltime 4wd. This system is similiar to the LC's. What it means is that unlike PT 4wd, power is distributed to all 4 wheels at all times. (it's something like 30 %front / 70% back or some figures).
You have several options while in 4wd.
locking center - 50% front/50% back: use when you are in slick conditions. but remember that it'll disable VSC (Vehicle Skid Control), so be careful when you want to use this feature... i.e. not sure if you'd want this disabled in the snow.
Low Range - 4lo: gives ya lots of power tackling those though inclines/declines and or difficult trails.
locked center and low: equal power to all 4 wheels and in low range for the extra stuff!
Some improvements. our 4wd system has the trac traction control which "helps to avoid slippage of the 4runner's driving wheels, which tends to occur during starting and acceleration on slipper surfaces, while maintaining an optimal driving force relative to road surface conditions. Utilizing both brake and engine throttle control, the system distributes torque to the wheel(s) with the most available traction and helps ensure vehicle control when starting or accelerating on slipper roads."
all that technical terms just means that we have an awesome 4wd system that'll help us get thru alot of the difficult trails

now our only limitation is height/approach/departure angles!