Just got my GT back from the Ford dealership. Vibration issue is a thing of the past. They used the RoadForce balancer on all the wheels and the car rides better than it has in quite some time.
They said they had to rotate one of the tires on the wheel and that a couple of other wheels were off by as much as ½ ounce. It's like night and day now.....rides smooth as silk at highway speeds.
Moral of this story....it seems that even when a tech is using the RoadForce machine, doing the balancing must be almost like an artform. The tech has to be an expert at it apparently. And at this Ford dealership they know what they are doing.
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