Doe anyone know if the climate control is run by vacuum or is it electronic. Just got the new truck last week and im getting very little air from the upper defrost vents and no matter what setting (floor, defrost, middle) i have it set at, the air always comes from the 4 main dash vents. Im afraid to take it back to the dealer now because we are leaving for a 900 mile trip this sat. to myrtle beach and dont want them tearing apart the dash to find the problem. If it happens to be electronic then maybe they just have to replace some part or something. Just wondering. The air cond and heat work fine but still comes from the main 4 vents the most. Craig