Engine Vibration and steer wheel vibration on highway

[ahennes01]

Hello-

I have an 03 pathfinder with 170k on it. I am in Minnesota and at times if snowing out etc I will leave it in 4 wheel auto on the highway. I noticed when in AUTO I get to about 60mph or so and the engine makes a slight noise when accelerating and the steering wheel has a slight vibration. As soon as I let off the gas it goes away. When I am in 2WD no issues at all. Its almost like its stuck in 4 wheel drive when its in AUTO.

Thanks for you help!