my new baby sounds sick! :(

hey guys! Been a long time lurker here and just joined since I finally got me a Tacoma! Love this thing!

All was great and rosy until recently (had this guy for a couple weeks only) when some weird noise appeared. It seems to happen only at low speeds when I hit the brake pedal, yet does not feel brake or engine related. Sounds like a whirr/vibration from underneath the front of the vehicle accompanied by rythmic clicking/clanking sounds. Transfer case going haywire for some reason maybe? I don't know, I'm not fully amiliar with this beast yet! FYI 4x4 hi-lo and diff lock all work fine.

It sounds like something is trying to shift, like the vibration is a lil motor and the clunking is whatever this motor is pushing trying to shift in place but clearly not working. I've read about transfer case TSB, would this be it? Previous owner did say transfer case got reprogrammed.

Anywhom, any help would be appreciated. Tried searching. Couldn't put my finger on anything like this and there's only so much reading one can do. I'm sure someone has had this issue before so a thread link would be nice. Straight up diagnostic even better!

Thanks in advance folks!