The tonneau cover industry likes to quote a senior-thesis type paper from university engineering students that even one of those improves aerodynamics by 10%.
And modern trucks aren't as bad as they used to be.
Modern trucks are better than they used to be, but they seem to give most of the efficiency back in terms of larger towing/payload capacity. It's absolutely bonkers how capable a "half ton pickup" can be equipped compared to 20 years ago.
The tonneau cover industry likes to quote a senior-thesis type paper from university engineering students that even one of those improves aerodynamics by 10%.
And modern trucks aren't as bad as they used to be.