The Ark II was built on the chassis of a dump truck. The truck was notorious for constantly breaking down between shots. It was also reportedly hard to operate in crowded areas safely because the placement of the windows was such that the driver of the Ark was unable to see clearly. The other vehicle, the Ark Roamer, was built on a Volkswagen van chassis from a modified "Brubaker Box" kit, and while it ran well, it had a limited range. The Brubaker group built both vehicles for the show.
There are no night scenes or episodes in "Ark II" because it was impossible to maneuver the Ark at night due to the lack of visibility from the driver's section. Also, each show had a 2-3 day turnaround, and Jose Flores was still a minor working under strict rules governing child actors. As a result of these factors, plus the Ark's tendency to break down, night shots for episodes were nixed.