TM 9-4120-411-14
B.1 GENERAL - CONTINUED.
j. Overhaul.
That maintenance effort (service/actions) prescribed to restore an item to a completely
serviceable/operational condition as prescribed by maintenance standards in appropriate technical publications(i.e.,
DMWR). 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 material
maintenance applied to Army equipment. The rebuild operation includes the act of returning to zero those age
measurements (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 to identify
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.
c. Column 3. Maintenance Functions. Column 3 lists the functions to be performed on the item listed in column 2.
(For detailed, explanation of these functions, see paragraph 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 the maintenance function at the indicated level of maintenance. If the number or
complexity of the tasks within the listed maintenance functions vary 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 maintenance allocation chart. The symbol
designations for the various maintenance categories are as follows:
C .........................................................Operator or Crew
O .........................................................Unit
F..........................................................Direct Support Maintenance
H .........................................................General Support Maintenance
D .........................................................Depot 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.
Column 6 contains a note number which shall correspond to the notes contained in
B.4 EXPLANATION OF COLUMNS IN TOOL AND TEST EQUIPMENT REQUIREMENTS, SECTION III.
a. Column 1. Reference Code . The tool and test equipment reference code correlates with a code used in the
MAC, Section II, Column 5.
B-2
