Can someone explain the 4x4 system for me. Thanks.

My wife decided to drive the expedition in to a field with about 5-6 inches of snow on it, but unknown was that there was also 5-6 inches of mud under it. So sure enough she got stuck and I had to come help. In rocking back and forth I noticed that only 1 wheel would spin on each axle. Eventually with the help of some hay I got it out, but the 4x4 seemed almost worthless if it slips that much.

I'm no master of 4x4 systems, so I'm guessing there are only limited slips in this truck and that when one wheel slips the other one gets no power? Is that correct. Even in 4Lo?

If that is right, what have you all used to get a real lock out. I looked up some air lockers but they are quite expensive.

Thoughts?

She didn't think it was funny when I could drive my audi through the snow and still have all 4 wheels turn even with one off the ground. I love the Expedition, but quattro is pretty awesome.

 

Complete with video

HowStuffWorks "How Four-Wheel Drive Works"

 

When it slips that much, it's usually due to the tires installed on it. If it had tires with an aggressive all-terrain type of tread then it's unlikely she would've got stuck at all.

 

The tires are basically new. It was a combination of manure/mud and snow. So the tread got caked up right away. I don't think anything other than some paddles would've done well in that crap.

 

What happened to you is normal. If you add lockers to your truck you will only break the axles, they were not designed for that much torque.

Everybody seems to think that 4x4 means that all four wheels drive. That is only sort of true. The differentials are open in the front so that you can steer. The rear may be a limited slip but they are worthless off road.

Quattro really isn't much different. It uses a center differential so the car can be 4wd on pavement. Depending on the vintage of your Audi you may be able to lock the center diff, the older ones circa 1985 also offered a rear diff lock. Today they use the ABS sensors to watch wheel speeds and the brakes are applied to slow the spinning wheel. This is great on road, not so much off road.

If you want a good description of the systems out there and how they work, visit my buddy Haralds site www.4x4abc.com

 

speaking of 4x4, the transfer switch i had was the one with a green filter in it so i switched it out with a blue one. when i put the new one on the tension in the switch was gone, there was no click in each turn, do i need to get a new switch or is there something i can do to fix it?