What a challenge.... Odd truck problem

The riddle you described appears to be the classic Odd Truck Problem. Here's a logical solution:

Assume that the trucks are labeled A, B, and C.

Park truck A next to the driver.

Ask the drivers of trucks B and C to swap trucks.

Have the driver of truck A drive away in the truck they were originally in.

By following these steps, the drivers will end up in their original trucks.