I've got a 17 Expedition that is about a year old with 15K miles on it. It's my wife's daily driver and she has never noticed this vibration but I have on a couple of occasions so it's not a constant thing. It seems to happen only in the morning on first startup as it runs fine after it gets going. Anyway, just drove it recently and it seems like it's missing at first as I was driving down our driveway which is about 250' long, then when I pulled out on the highway it actually felt like the tires had flat spotted but the frequency of the vibration was too rapid for the speed I was going to be flat spots on the tires . It actually was causing the steering wheel to snap left to right in my hand by about a 1/4". Less than half a mile down the road it was gone and it ran fine. I am inclined to think it's missing and nothing to do with the tires though that's what it feels like. I am new on the forum and did a search but nothing popped up. Just wondering if anyone else had experienced this. I was initially not to keen on having a V6 ecoboost but being a Ford guy I had to accept it and it does seem to have plenty of power but I am inclined to believe it's just the engine struggling to do the job at startup. Just wondering if any other owners had experienced this? It's about due for an oil change and I plan to have them hook up their gizmo and see if it's thrown any codes. Thanks

 

Have you tried lightly pressing the brake pedal when you feel this? Maybe a caliper slide is sticking a bit and frees up when it gets a bit of heat? Just a thought.

 

Thanks for the tip, I'll try that. You could be right as you have to depress the brake as you hit the start button and maybe I am depressing too hard and it's hanging up...