3D printed trucks, with a base coat on.
You can't see in the photo, but there are subtle print lines visible. These were printed not with resin but the cheap stuff.
Now, I'd infinitely prefer GHQ detailed trucks for my combat units. But for a supply train, or a convoy game where I need loads, these become much more attractive. I don't have a 3D printer (yet) but if I did need, say, 100 trucks, these would be plenty good enough for temporary use.
And I'm sure the smart folks at GHQ are watching all this closely. After all, it's the modeling skill that sets them apart, not the ability to cast metal (though they do that very, very well).