I also have the same problem and had my transmission flushed the cv joints replaced and it did not solve the problem. My impression is that it has to do with the awd because it is worse while turning, and better while turing on gravel than blacktop where the wheels are able to slide. The vibration is too high frequency to be a drive shaft vibration at low speeds. I would like to turn off the limited slip differential in the front end and then drive the car but I don't know if that is possible. That will tell me if the awd was trying to keep both wheels spinning at the same speed and there is potential that the left or right sensor that determines wheel speed is bad and the car thinks that one of the wheels is slipping because it is moving faster than the other one. I have looked for these sensors but the only thing that makes sense to me is the magnetic sensor near the caliper that engages the abs system could be used to determine if one wheel was rotating faster than another one. can anyone answer this?