TM 9-4120-360-14
MAINTENANCE ALLOCATION CHART
B-1. General
a. This section provides a general explanation of all maintenance and repair functions authorized at various
b. The Maintenance Allocation Chart (MAC) designates overall responsibility for the performanace of maintenance
functions on the identifed end item or component. The implementation of the maintenanance functions upon the end item
or component will be consistent with the assigned maintenance functions.
B-2. Maintenance Functions
a. Inspect. To determine the serviceability of an item by comparing its physical, mechanical and/or electrical
characteristics with established standards through examination.
b. Test. To verify serviceability and detect incipient failure by measuring the mechanical or electrical characteristics
of an item and comparing those characteristics with prescribed standards.
c. Service. Operations required periodically to keep an item in proper operating condition, i.e., to clean
(decontaminate), to preserve, to drain, to paint, or to replenish fuel, lubricants, hydraulic fluids, or compressed air
supplies.
d. Adjust. To maintain, within prescribed limits, by bringing into proper or exact position, or by setting the operating
characteristics to specified parameters.
e. Align. To adjust specified variable elements of an item to bring about optimum or desired performance.
f. Calibrate. To determine and cause corrections to be made or to be adjusted on instruments or test measuring and
diagnostic equipments used in precision measurement. Consists of comparisons of two instruments, one of which is a
Certified standard of known accuracy, to detect and adjust any discrepancy in the accuracy of the instrunent being
compared.
g. Install, The act of emplacing, seating, or fixing into position an item, part, or module (component or assembly) in
a manner to allow the proper functioning of an equipment or system.
.
h. Replace. The act of substituting a serviceable like type part, subassembly, or module (component or assembly) for
an unserviceable counterpart.
i. Repair. The application of maintenance services or other maintenance actions to restore serviceability to an item
by correcting specific damage, fault, malfunction, or failure in a part, subassembly. module (component or assembly),
end item, or system.
j. Overhaul. That maintenance effort (services/actions) necessary to restore an item to a completely
serviceable/operational condition as prescribed by maintenance standards (i.e., DMWR) 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 material maintenance
applied to Army equipment. T'he rebuild operation includes the act of returning to zero those age measmements
(hours/miles, etc.) considered in classifying Army equipments components.
B-3. Column Entries.
Columns used in the maintenance allocation chart will be limited to those shown. Entries for those columns are
explained below.
a. Column 1, Group Number. Column 1 lists group numbers, the purpose of which is to identify components,
assemblies, subassemblies, and modules with the next higher assembly.
b. Column 2, Component/Assembly. Column 2 contains the noun names of components, assemblies, subassemblies,
and modules for which maintenance is authorized.