Blockland vehicles: Not made of bricks. Lol.
Besides, a lot of those bricks you mentioned (DON'T 24-IPLE POST, IT'S JUST DUMB) don't exist within Blockland, particularly the wheel bricks, the axles, and the oddly shaped ones. (non-rectangular, not-perfect-circles)
Blockland vehicles are made with computer models, and scripts, both of which are pretty hard to make.