[edgineer]

That's opinion/stereotype, and unsupported. From Rob Cockerham's experiment (2002):

"I guessed that 98% of all truck beds are empty"

"In 25 minutes I had counted 150 trucks, and 99 of them had been empty. This 66% empty ratio was much lower than I had expected. I hadn't realized that so many trucks were being so successfully utilized."

"The results were similar: 39% of the trucks were hauling goods, and 61 of them were empty"

"Along with this adjustment of my perception, I also realized that an empty truck is no more wasteful than an empty back seat. Most cars AND trucks in the US drive around with 75% of the cargo space unutilized...what difference does it make if it is interior or exterior space?"

https://cockeyed.com/science/data/truck_beds/truck_beds.html

[wooger]

A vehicle thousands of pounds heavier, with much worse mpg, and almost by definition terrible aerodynamics, is no less efficient than a car with empty rear seats? Sure.

[Der_Einzige]

The only part that matters is the weight. https://en.wikipedia.org/wiki/Fourth_power_law

[PunchyHamster]

I'd imagine that % changes heavily on hour in the day and road observed.

People using truck for work (tradesman etc) do it all thorough the day. People who just use it as status symbol get to work and back from work at given hour. Also probably more usage in weekend when people doing weekend project go shop and people not doing that don't even get out on the longer trips.

Sitting on one road for an hour (and looking at photos, far from peak traffic) is near meaningless

[potato3732842]

The "peak traffic" that all the 9-5 office workers on HN see is also not when trucks that carry things move. Blue collar work usually starts at 6/7/8am.