Some causes of wheel vibration are not visible.
First, do you have access to a torque wrench? The lug nuts should be at 76 ft. lbs. -- any higher and it may cause problems. It costs nothing to check them (unless you need to buy a torque wrench, which is good to have anyway

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Next, when were the tires balanced last? If more than 5,000 miles, it could be contributing.
Have you rotated the tires? If not, you could try swapping the fronts to the back and see if the vibration moves with it.
Also possible that the wheel bearings are bad.