Two fold... Will a white vehicle retain heat throughout the night, thus being warmer come morning? While a dark truck, with dark tinted windows and dark interior, lose heat heat faster throughout the night?
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$\begingroup$ Why would you think that a white vehicle retain heat during the night? Or the dark truck will lose heat faster? Can you give explain your assumptions? $\endgroup$– user190081Commented Sep 22, 2018 at 16:27
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$\begingroup$ You are referring to the effect of a white or silver coat reflecting infrared. This effect is used in a thermos to keep the contents hot or cold. This also requires a heat insulation (like vacuum in a thermos). Without insulation, the temperature under the white paint would be higher due to reflections thus canceling their heat keeping effect. So the paint color would not substantially affect the cooling time (starting from the same temperature). $\endgroup$– safesphereCommented Sep 22, 2018 at 16:51
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The misunderstanding comes from the fact that for the same car, in the sunshine, if it is painted white it will not heat up as much as a car painted black. This is because white reflects a lot more of the sunshine falling on it, whereas the black painted car absorbs much more and heats up more.
Electromagnetic radiation from the sun at the surface, red part of the plot, has a lot of energy in the visible which can be reflected by paint.
This is not a reversible scenario for the black body radiation of the cars at night, which is how the car cools. The black body radiation of the night temperatures that the cars have has very low frequencies, in the infrared and microwave, not the visible:
The paint has no effect on the radiation which will cool the two cars.
