Try it in 4lo in loose dirt and see if it engages. Give it a little spin and see of your front wheel digs. Only one will spin if it is locked. It will spin very easy in 4lo so sneak up on it with light stabs at the throttle.
If it does spin a front tire, your actuator is not the problem.
If your front does not spin, then you need to get a little deeper. Your actuator could be the problem, but the banging might be the rotary encoder or actuator not working correctly. I can't remember the manual off the top of my head, but I doubt the shifting logic will engage the front axle if the transfer case is not shifting.
A little "graunch" or clash when engaging Isn't abnormal.
Banging, crunching or grinding and failure to engage is a more serious problem.
Shift forks and actuators on push button transfer cases are likely culprits and gets expensive fast.
Test it out in 4lo before spending any cash and see what you get.
Make sure you are somewhere you can at least get home from in 4lo when you try it. If it goes in and won't disengage you're up the creek. At home in a gravel driveway would be best.
Cheers
(as of now)
