IIRC, Thai has a post in one of the sub forums.
AWD: no low range gearing, has a center differential which allows all the wheels to receive power and turn at different speeds. Unibody Toyota SUVs are AWD.
4WD: it has low range gearing, all Toyota trucks and (truck based) SUVs that are 4x4 are 4WD, some are part-time while others are full-time.
Full-time 4WD: has low range gearing and a center differential, which allows it be driven with power to all the wheels to receive power and turn at different speeds. Locking the center differential in makes it behave like a part-time 4WD vehicle because all four wheels rotate at the same speed.
Part-time 4WD: has low range gearing and no center differential, all four wheels recieve power, but cannot turn at different speeds. Thus part-time 4WD drive systems should not be operated on dry pavement, since it'll cause excessive and unneccessary wear on the driveline and/or tires.
TORSEN: stands for TORque SENsing. Both V6 and V8 4WD 4Runners have this. TORSEN center differential is what allows the 4Runner to split it's power upto 71% to the rear and 53% to the front under slippage conditions with a normal 40/60 front/rear split under normal conditions.
With that said, the 4th gen V6 4WD 4Runner in 4H is no different than the V8 4WD. I stick by my statement that the 4th gen V6 4WD 4Runner is a full-time 4WD with the option of 2WD.
