Hey Smitty (I assume that's what HSmith stands for right?) - have a good look at the owners manual and search for threads relating to the use of the 4wd system here and elsewhere. Using it improperly will result in significant damage and you won't be pleased.

It's not all that complicated but it's important to understand how your truck (it's a truck not a car mind you) operates.

You'll avoid costly repairs and learn to use your truck to it's full potential. More importantly, you'll actually learn to DRIVE it as opposed to simply operating it.

Good luck.