Did your doctor have any ideas as to why it would happen only while driving your truck? Seems odd a vitamin deficiency would only show symptoms in one isolated scenario especially when you say it doesn’t happen while driving your car. In either case glad you are getting some answers.
I also starting getting dizzy a few weeks ago and went to the doctor but they didn’t find anything. Chalked it up to the fact that I always have ear problems and I wrnt swimming the day before I started getting dizzy. I also drive a tundra though…