In general, a CDL is required for any vehicle that is over a certain weight or that is used to transport hazardous materials. Fire trucks typically fall into one of these categories, so it is important to check the specific requirements for your area.
If a CDL is required, the mechanic will need to obtain the appropriate license before they can road test fire trucks. The process for obtaining a CDL can vary from state to state, so it is important to research the requirements in your area.
In some cases, a mechanic may be able to get a temporary or special permit to road test fire trucks without a CDL. However, this is not always the case, so it is important to check the local regulations.
It is also important to note that even if a CDL is not required, a mechanic should still take the necessary precautions when road testing fire trucks. This includes following all traffic laws and regulations and being aware of the risks associated with driving a large, heavy vehicle.