TM 9-2320-272-24-4
B-2. MAINTENANCE FUNCTIONS (Contd)
j . Overhaul. That maintenance effort (service/action) prescribed to restore an item to a completely
serviceable/operational condition as required by maintenance standards in appropriate technical
publications. Overhaul is normally the highest degree of maintenance performed by the Army. Overhaul
does not normally return an item to like-new condition.
k. Rebuild. Consists of those services/actions necessary for the restoration of unserviceable equipment
to a like-new condition in accordance with original manufacturing standards. Rebuild is the highest degree
of materiel maintenance applied to Army equipment. The rebuild operation includes the act of returning to
zero those age measurement (hours/miles, etc.) considered in classifying Army equipment/components.
B-3. EXPLANATION OF COLUMNS IN THE MAC, SECTION II
a. Column (1) - Group Number. Column 1 lists functional group code numbers, the purpose of which
is to identity maintenance significant components, assemblies, subassemblies, and modules with the next
higher assembly. End item group number shall be "00."
b. Column (2) - Component/Assembly. Column 2 contains the names of components, assemblies,
subassemblies, and modules for which maintenance is authorized.
NOTE
Those components that are unique to M939A2 series vehicles are
identified in column 2 by an asterisk (*).
c. Column (3) - Maintenance Function. Column 3 lists the functions to be performed on the item
listed in column 2. (For detailed explanation of these functions, see para. B-2.)
d. Column (4) - Maintenance Category. Column 4 specifies, by the listing of a work-time figure in
the appropriate subcolumn(s), the category of maintenance authorized to perform the function listed in
column 3. This figure represents the active time required to perform that maintenance function at the
indicated category of maintenance. If the number or complexity of the tasks within the listed maintenance
function varies at different maintenance categories, appropriate work-time figures will be shown for each
category. The work-time figure represents the average time required to restore an item (assembly,
subassembly, component, module, end item, or system) to a serviceable condition under typical field
operating conditions. This time includes preparation time (including any necessary disassembly/assembly
time), troubleshooting/fault location time, and quality assurance/quality control time in addition to the time
required to perform the specific tasks identified for the maintenance functions authorized in the MAC. The
symbol designations for the various maintenance categories are as follows:
C .......................................
Operator or Crew
0 .......................................
Unit Maintenance
F .......................................
Direct Support Maintenance
H.......................................
General Support Maintenance
e . Column (5) - Tools and Equipment. Column 5 specifies, by code, those common tool sets (not
individual tools) and special tools, TMDE, and support equipment required to perform the designated
function.
f. Column (6) - Remarks. This column shall, when applicable, contain a letter code, in alphabetic
order, which shall be keyed to the remarks contained in section IV
B-2
