2011 F-150 Lariat Ecoboost 140k miles.

I've got a reoccurring vibration coming through the steering wheel. It feels and sounds like a mechanical speedo cable when the lube ran out. It is intermittent. I can't ID any specific speed, gear, temp, etc when it happens. Usually only lasts a minute or two at a time and not every time I drive it. Seems to go away on its own. My regular commutes usually include a mix of highway speeds, at least for short distances. A solution would be great, but even any suggests for things to look for when it happens or pay attention to while I try and pinpoint what is going on would be greatly appreciated!