Which aspect of a truck is NOT considered in its distinguishing characteristics?

The distinguishing characteristics of a truck typically focus on structural and design elements rather than performance metrics like engine performance. When assessing the characteristics that set a truck apart, elements such as the solid framed structure and single frame design are fundamental as they influence the overall build and utility of the vehicle. Gross Vehicle Weight also falls into the category of structural specifications, as it is indicative of the truck's capacity and design purpose.

In contrast, engine performance relates to how effectively the truck operates, which while important for functionality, does not directly define its distinguishing physical characteristics. Therefore, engine performance, as an aspect of the truck, is not a defining feature in the context of distinguishing characteristics, making it the correct choice in this scenario.