possible numbering system
I'm not sure if this could be the case, but in some counties, the first number of all fire units relates back to their assigned FDID number. This is a statewide numbering system that is used in reporting our fire data to the state. The first digits are the county's alphabetical number that used to be prevalent on our license plates. The next three digits are the department identifier, also usually alphabetical. Here in Newton County, my department (Brook VFD) is 56-001. All of our helmet and truck numbers correspond with this system. Helmet numbers would be 56-101, 102, 103, etc. Trucks are numbered the same way, 107, 112, 113, etc. Goodland VFD is 56-002 and they number everything beginning with a 2. The exception to this rule here is that EMA many years ago was assigned the 600 series of numbers throughout the state, so Morocco, 56-006 actually uses the 700 series of numbers and our EMA has the 600's.
Here is a link to all FDID numbers for Indiana fire departments. Now, do not assume every county is numbered in this manner. I'm just saying its a possible method. Some counties do not have any uniform numbering, such as my neighbors in Jasper County. They simply use "Pump 3" or "Tanker 1" or "Brush 2" for each department. But since each department is dispatched on a different frequency, it doesn't cause too much confusion. When you have a county-wide dispatch frequency or central dispatching, the dispatchers have to have a way to distinguish between departments and this is one possible numbering method.
IF...and I said IF...this is how Clinton County were to number their departments, the truck in question would have been from Perry Twp. VFD in Colfax. However, the news reports I looked up while posting this do not list that department as responding to the fire I think Tim is referring to in Michigantown.
http://www.in.gov/dhs/files/firedepts.pdf
