So, call me stupid, but what is the difference between Four Wheel Drive and All Wheel Drive?

Advertising! Unless I'm wrong which I may be! Audi calls it Quattro, Trucks call it 4x4, Subaru calls it AWD. The only difference I can dream up is that Quattro, AWD and the like are always on whereas 4x4 is switchable, but in my limited experience I don't think even that is true. All goes back to the marketing department.

Scot

I owned a bravada, which is all wheel drive, and it worked great. It is in 2 wheel dr, until a sensor denotes a slippage, and it immiediatly kicks in "all wheel", or the wheel that is slipping. This really works good, but the olds doesn't have solid 4 wheel dr, or 4 wheel LOW. If you want to use your car to pull out a small stump, or large bushes, it works really good with 4 wheel low. My trailblazer has 2 w/d , auto 4w/d, 4w/d hi, and 4w/d low. My wifes Explorer only has 2w/d, and auto 4w/d, and 4w/d low.
4w/d low has a lot of pulling power.

I probably didn't help you much, but they are quite different.

If you are in a gravel parking lot, and have it in 2 w/d the car turnes a circle normally. If you change it to 4 w/d auto, it will still turn normally, but if there is a slippage, another wheel will carry more of the load. In reg 4 wheel drive, it feels like your car is trying to tear itself in two. It is hard to describe, but that is how it feels. In 4 w/d LOW, you think you just tore it in two. The two inside wheels will spin a little, in the rocks, and the two outside wheels will slip a little, in the rocks. If you are on concrete, the car doesn't want to move in a sharp turn, as the wheels are locked. With auto 4w/d and all wheel dr, there is no problem.

The easiest way to explain, is to get in one and try it. I'm sure it will fool you...

|UPDATED|7/11/2002 4:53:19 PM|/UPDATED|

Lets complicate this a bit... My Jeep has "2 WD" ,"part-time 4WD" ,"part-time 4WD-Lo" and "Full-time" 4WD. "part-time" locks the front and rear drive shafts (not for use on pavement). "full-time" allows you to drive on the road without hurting the drive train. There's some sort of slipping differential between the front and rear driveshafts. Jeep also offers 2 other types of 'FULL-TIME" systems. System 1 will put power to any of the 4 wheels which has the most traction. System 2 act like my system where power is supplied to the front wheels if it detects that the rear wheel is slipping. I believe the Audi's works similar to the Jeep system 1 I described above.

The euro car market,,,audi,bmw etc.use a very sophisticated awd system. They employ a viscous coupling that allows operation of their system with none of the problems usually encountered in a 4wd setup. Let me point out that the use of this type coupling is finally finding its way into us vehicles. Without it the standard 4wd does want to tear it self apart and is quite dangerous to operate on dry roads. When a 4wd is fully engaged you have all 4 tires trying to run at different speeds. This is due to the fact that NO set of tires is exactly the same size. The result is a tendency to cause the system to bind up in dry hard road conditions and yet work really well in slippery conditions. My wife drives a 325IX series bmw that is very hard to find in the us,,,this car is tons of fun in the snow or wet.The system allows economical safe operation in all conditions with no problems with tire wear nor turning .

Geo