[Bowler]

I have a 2004 Explorer that is 4WD with a V-6 and auto transmission. On the dash, I have 3 buttons. 4WD AUTO, 4WD High and 4WD Low. Is 4WD Auto the same as AWD? Why not just put it in 4wd high when conditions on road are slippery or when you need traction?

[ebaines]

Different manufacturers may use different terminology, but the basic difference between AWD and 4WD is that AWD is usually part-time, available when the car senses slippage at one end of the car and automatically transfers power to the other. 4WD on the other hand is permanent, with all 4 wheels receiving a constant portion of the engine's torque. 4WD Low is for low gear, high torque requirements ("stump pulling"). On your car my guess is that "4WD Auto" is essentially AWD, where the car's electronics try to figure out whether two-wheel drive is appropriate or to split the power in some fashion to all four wheels.

[TxGreaseMonkey]

Good answer, ebaines.

[Bowler]

That's kind of what I figured, but I wasn't sure. Manual doesn't tell you much. Thanks for the answer

[harryletterman]

That's kind of what I figured, but I wasn't sure. Manual doesn't tell you much. Thanks for the answer

Hey there Bowler, though I can help you with that as well.

Both AWD and 4WD drive all four wheels so in one sense there is no difference except that AWD has become an accepted description for a car that drives all of the wheels, all of the time. 4WD is generally accepted as a car or more typically a larger SUV (Sports Utility Vehicle) that uses a driver selectable system that mechanically engages the drive to all four wheels.

4WD is normally used on large SUV Four-Wheel Drive (4x4) vehicles designed to use the extra traction of 4WD in off road situations. These vehicles are predominately truck based platforms with large wheels and off road tyres that combined with a manually selected and a locked 4WD driveline enables the vehicle to venture off-road and negotiate very difficult terrain.

Hope that gave you some more information on topic :)

Thanks, Harry

[Bowler]

Thanks Harry for elaborating on this subject.

[smoothy]

To add to that... AWD and 4WD are different in another aspect... AWD is actually what is permanent... where power is split between all the wheels in percentages depending on how its designed... but power does go to all four wheels all the time (usually). 4WD you will have a means to select between 2WD and 4WD... be it a switch or a lever. The front hubs may or may not have a means to unlock them so that's another subset of 4WD... AWD (meaning ALL Wheel drive) might have a means to lock the center differntial... but NOT select between 2 and 4 wheel drive.

I drive both types regualarly. A Dodge Dakota can come in a AWD version... whereas an older Chevy (just two examples I'm tossing out) most times will be either 2WD or 4WD. Jeeps can get rather confusing as certain modles have come in all three versions over the years. 2WD, AWD (Jeep called that Quadratrac in the past) or the good old 4WD.

I've got an AWD Dodge Dakota truck AND a mid 80s GM 4WD truck setting in my driveway right now.

[Bowler]

I am old school where you used to have to manually put the vehicle in 4WD. I understand the 4wd HIGH RANGE and the 4wd LOW RANGE, but it's the 4wd AUTO that confused me. What does AUTO mean in this case? There is no way to take the vehicle out of 4wd. Maybe AUTO means it switches from 2wd to 4wd as needed. It seems to work though.

[smoothy]

Could be... I'm not at all familiar with the Fords... Because AWD and 4WD can both have a two speed transfer case... but not all do. The car based vehicles it tends to be more rare on (I can think of many that don't but they tend to be front wheel drive variants). Most truck based one will usually have it. (can't think of an example that doesn't)