Abstract: In the operation of a dump truck (10) it is often desirable to have an indicating means (24) provided to indicate to the operator when the truck body (14) of the vehicle is in its elevated or dumping position. It has been common practice to attach an indicator to the truck body that is visible to the operator when the truck body is down, however, this fails to provide a warning, as such, unless the operator remembers to take note of its absence before he drives away should the truck body fail to return properly. Also electrical indicators have been provided to indicate the position of the truck body, however, they rely on switches and other rather delicate componentry which is subject to damage due to the harsh environment which exists in the operation of the dump truck.