Grinding noise/vibration

I'm getting a vibration with a grinding noise from the front end of my truck. It first started out only when cold and pretty subtle, now it is much worse and I can feel it through the body of the truck and the steering wheel and can hear it too. It does smooth out after driving for a while. It also remains the same whether i'm accelerating, coasting, or braking.

What really confuses me is that it goes away totally in four wheel drive. So that means it has to be foreward of the transfer case I'm thinking.

Also, It happened with both my stock wheels/tires and my new set of wheels and tires. I changed my driveshaft too and that had no effect on this vibration.

Anyone have any thoughts? I tried to take it to the dealer but they basically said they didn't want to touch it because it is lifted so I'm going to an offroad shop on Wednesday and hopefully they can figure it out. If it is the differential or transfer case I'm really hoping that its covered under my extended warrenty which is good for another 20k miles

 

Oh yeah, this just randomly developed after having my lift already installed for about 9 months. I've got about 3" of lift too

 

...Wheel bearing? Jeeze I dunno. Maybe a hub? could even be a ujoint

 

Metallikatz3 - Wondering the outcome of this issue.Having the same issue w/02 Tacoma right after the lift I also noticed the grinding however I feel it more than I hear it.All the symptoms seem to be the same.