I'm not a gearhead at all, but I like to know how stuff works. There are a few good articles online for how automatic 4WD works, although it's a little difficult to figure out which specific implementation is used in the new 2013s.

So, two questions:
* Is there a good reference for how 4WD auto works in the 2013s? I want to understand what physically (or electronically) happens when you flip the **** from 4WD auto to 4WD high, etc.
* Is there a good technical reference for all the systems in the 2013s? I get the urge to research a different part every couple of days (the last time it was "how does a limited slip differential work"... noobish, I know), and having some starting point, even if it's a little over my head, could make the process a lot quicker.

Thanks!

 

Look at it this way - vehicles with Auto 4wd have a transfer case that works like a differential. In Auto, it's like a limited slip and in "regular" 4wd it's locked.

 

That's what I figured, but there was some ehow article about a sensor on the front axle to detect rotational differences from the back. That seemed... complex, so I thought maybe I could find out why it would be necessary (if it even applied).

 

It's necessary to determine how much torque to apply to which end. It's like an electronically controlled limited slip.