This is even more likely if you're running one or more spacers.
McMark dropped my car off at my house last night (now *that* is customer service!

So today during lunch break i took the front wheels off and found that the second spacer on the drivers side was wobbling by a good mm left to right.
I cleaned all surfaces, put it all back together, made sure there was no wobble and voila:
Smooth like butter up to 120 ...

