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That 0.34 is applied to a huge frontal area though. Ends up having lot more drag then a sedan because the truck needs to move a lot more air molecules out of the way.

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(FTR, I jumped the gun on my answer and I was wrong - the actual relevant performance figure is the product of the coefficient times the frontal area, so the parent is correct, it might perform much worse in practice than a smaller car with the same CD)

That's not how it works. A car's drag coefficient is calculated in a wind tunnel, and takes into account the entire body shape.

The frontal area can also be very deceiving, a new VW ID Buzz for example has a CD of 0.285 despite a massive front.

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