Originally Posted by BavarianE39

Hello, AWD and 4x4 are a bit different. Every car maker has different AWD systems when it comes to their cars: Xdrive, Quattro, 4matic, ect. The AWD system in your 2002 x5 is a standard full time AWD meaning it has a constant 38%Front/62%Rear torque split I believe, both front and rear differentials are open with no limited slip, and the transfer case is also open, non lockable.

4x4 systems generally give you an option to go 2wd or 4wd and offer low gear and locking differentials and transfer cases. 4x4 is great for going off road or going through mountains of snow. AWD systems are more suited for slightly less off road activities. But don't get me wrong, Our X5's can still plow through snow and mud with the right set of tires.

And to answer your stuck in mud question, both 4x4 and AWD will have 4 wheels spinning, the AWD will have varying speeds on all 4 tires depending on the amount of traction, while the 4x4 system can lock all wheels to spin at the same speed.
Hope that helps!