I have noticed the same thing on mine . It's a very subtle shake I think shiver would be a good description . For me it does it when I hit 40 only for a split second. It doesn't matter if I hit it on acceleration or deceleration. And the weird thing is that it's sporadic.
Have you noticed how close to a lane divider or the shoulder you are? All of these I've seen so far have ended up just being the lane keep assist vibrating the steering wheel.
