A 2014 Jaguar XJ-L 6 cyl supercharged 4 door sedan…. really is one of the worlds most beautiful cars. As a result of driving from the Philadelphia PA area to a small town south of Charlotte, NC with two passengers I developed “Internal Tremor”. See the study HERE. Quoting from it: “…. should the seat be exposed to high vibration magnitudes, it might not perform very well, resulting in a poor “ride” for the occupant. An example of this type of case is a luxury car which is driven on relatively smooth surfaces (asphalt roads) and has a high specification suspension.

Ψ = ss + fst + dva + itvta

where Discomfort Ψ  = Static Discomfort Constant + Fatigue Constant + Vibration Discomfort Index + (Interaction Constant x Time x Frequency Weighted r.s.s. [Repeated Sprint Sequences] Acceleration)”

My response during the ride was the feeling that the tires were out of balance. The tremor appeared: during the ride, several hours afterward while sitting at the dining table and when I reclined in bed about three hours later. There is no guarantee you will experience the same thing. The internal tremor did not appear during or after the ride home which was driven at even higher speeds than the initial ride. the road surfaces vary from very, very smooth to rough over concrete being prepared for top coating… Cracks in the road, potholes, swerving from lane to lane in response to traffic produce accelerations that the body has to withstand during the drive in addition to the factors in the equation above. All add to the discomfort of driving. What about the tension of driving in high speed traffic? The constant stream of perceptions related to the positions of other traffic and their weaving and bobbing which cause reactions which add to the tension in addition to the vibrations as the car and it’s systems respond to the road. Negotiating a curve produces lateral accelerations in addition to the other forces acting on the body.  It’s a constant struggle to drive in traffic as you have to predict and respond to the actions of the other vehicles, all driven by a cross-section of great drivers all the way down to idiots behind the wheel with nio way to know who is driving the other vehicles.