When four-wheel drive is engaged, the front tires grind and then lock up?

You either have a CV axle that is bad, or the front differential needs to be rebuilt, let's start by removing the front CV axles for inspection, here is how the job is done. With the axles removed try spinning the wheels to see if they rotate smoothly. Check out the images (below). Please upload pictures or videos in your response to the problem so we can see what's going on.

Alaska must be quiet at night :) no problem on the delay let me know how it goes.