Speed related clicking sound from front end

[Rukee]

Hey everyone. I have a 2000 Tahoe that just started making a clicking sound in what sounds like the right front. It's speed related, the faster I go the faster it gets. It almost sounds like the axle is trying to engage. I replaced the actuator on the front axle with the same results. If I jack the front off the ground turning each wheel there is no sound, also turning the driveshaft from the transfer case has no sound. Any ideas of what be going on? Thanks in advance for any responses.

 

[Rukee]

Found the issue, even though it sounded like it was in front, it's the transfer case. Any ideas where to get a rebuilt one? It's a 5.7L with the push button 4x4 in the dash.