A remarkable drive system that supplies equal power to the front and rear axles. 4WD IS NOT THE SAME AS AWD
1.Equal power is disributed to the four wheels AT ALL TIMES (however this will sacrifice turning ability if you leave the vehicle in 4 wheel lock while taking a corner on PAVEMENT and don't put the hubs in free or put it in 2wd)
2: 4x4 vehicles CAN be driven offroad( Rally courses are no more than gravel roads and not anywhere close to offroad conditions)
NOT ALWAYS BAD ON GAS, some 4x4 vehicles have smaller engines and get great mileage without sacrificing ability(toyota landcruiser). However, my '78 blazer has a 6.6L engine with a 3 speed and gets 12 MPG in the city.
The concept of a 4x4 vehicles existed Prior to WWII but the technology was never fully exploited until the USA developed the willys jeep to bridge the gap between halftracks and cars for an adaptable vehicle that didn't get stuck easy but went faster than a halftrack and to compete with the Volkswagen 'THING' .
4WD vehicles are basically Rear wheel drive vehicles that have an extra drive shaft to power the front wheels. The driveshaft that powers the front wheels runs off the rear driveshaft using a transfer case that splits the power evenly between front and back when engaged.
Nowadays few people recognize the ablility of 4x4 vehicles
and rarely put 4x4's to the test( stereotype moms in a Hummer h2 driving her kids to school 2 blocks away)
Top 5 4x4 Vehicles of all time in RANDOM order:
-Land Rover 1995 and prior
-Toyota Landcruiser (new fj40 excluded)
-Chevy K5 Blazer/GMC Jimmy(full size only, small sizes excluded)
-Jeep (TJ/YJ and Willys)
-Original Hummer (H2 and H3 excluded)
4x4 Vehicles that are everything a 4x4 vehicle is supposed to be include: Land rovers 1995 and prior, Toyota Landcruisers, Ford Broncos (full size), Jeeps (most models minus Commander and 4 doors), ORIGINAL HUMMERS(H1, US Army), Chevrolet K5 Blazers(small size excluded), GMC Fullsize Jimmys (1991 and prior), Suzuki Samurai, Shortbed 4x4 pickups, Toyota tacoma(iffy)
4x4 Vehicles that rarely/never use Four Wheel Drive and take away from everything 4x4 vehicles are supposed to be include: Porsche Cayenne, Nissan Pathfinder(I've never seen or heard of one going on terrain rougher than a golf course or gravel road), Hummer H2 and h3, All Lexus Kia Mercedes BMW and similar SUV's.