I have a vibration in the steering when the HVAC is running hard. Took it in to the SC, they made it significantly better, but still there. I watched them as they worked on it, so was able to confirm no pipes or hoses resting on the steering shaft. It's just that AC motor vibrates quite a lot, even tho it's mounted on bushings. I still wonder if the behavior mine exhibits, is all that normal or not. I'll probably asked other locals about there experiences some more.
You may have your Service Center, check yours out too. They know what to look for.