Also, the one I bought here in Brazil has its scale 1/36. Since I could not compare to the real game (shipping takes time), I made some calculations based on images and the box size (12"), and 1/36 must fit better than 1/24 (too big).
Thanks for the links! My truck is from the same company, but not as nice as the ones you have shown. I like the extra details, like the full back bed, rear view mirrors, etc. I think my truck version is around 1/48 scale. If the nicer versions you have given links for are the same scale, I may have to upgrade
Indeed, I also found this truck at my local Wal-Mart. It is by Maitso and is 1/36 scale as indicated on the bottom of the truck. Here is a picture of the truck in the packaging, and un-finished. It cost about $3.50.
All this talk about trucks got me interested in scale on the off chance I wanted to build a zombie town. The minis look to be 28mm (as are most metal figs).
Anyway, I found an interesting discussion on scale here: http://theminiaturespage.com/boards/msg.mv?id=51867, but I don't agree that 1/64 is the best compatibility with 28mm figures. Take a look at the pic. The truck is 1/46 and the GTO is 1/50.
Take a figure with you to the store b/c not all the Maisto cars/trucks are the same scale. I got a Mustang (in box) that was 1/39 and IMO it's too big. Take a look at the pic. Plus, I'm happy with a red truck.