Depends on the angle of the sun, how daylight strikes it, cloudy or clear skies, what it's settin' next to, the phases of the moon, what the primary color is . . . .
Both of my truck are forest green/driftwood. When I ordered the '99 truck, the driftwood on the sales brochure looked light tan. Ok, beige then. When the truck came in I thought it had been mis-painted. Guess not. Looks silver/gray most of the time to me.