Troubleshoots, performs maintenance and major repairs on heavy-duty mobile equipment, combat, tactical and automotive vehicles. This may include self-propelled artillery, tracked cargo and personnel carriers, road graders, mobile cranes, front loaders, conveyors, bulldozers, power shovels, compressors, generators, tanks, tracked combat vehicles, sedans, buses, all terrain vehicles, trucks, semi trailers, forklifts, tractors, and accessory equipment. Troubleshoots, repairs and overhauls major systems to include internal combustion engines, turbine engines, automatic and non-automatic transmissions, heavy duty drive line systems, and hydraulic utility systems and controls. Makes repairs to assemblies and components such as voltage regulators, generators/alternators, brake cylinders, etc. Performs work in accordance with modification work orders, technical manuals, lubrication orders, maintenance bulletins, regulations or management policies. May repair a variety of more complex major systems to include engines, cross drive or similar multi-system transmissions and a variety of intricate fuel injection systems. Troubleshoots equipment and diagnoses the cause of mechanical failures by means of visual and auditory checks and/or uses test equipment such as engine analyzers, compression testers, voltmeters, ohmmeters, pressure gauges, and computer diagnostic tools. Utilizes embedded diagnostics in equipment and a wide variety of original equipment manufacturer system analyzers in order to determine the exact nature or extent of repair. Determines what adjustments may be necessary to complete work orders, and whether any additional repairs other than those specified or indicated on the work order are necessary. Removes and disassembles engines and major assemblies, sub-assemblies, components, and fuel, hydraulic, and oil pressure systems. Makes the appropriate repairs, overhaul, or modifications in accordance with the proper repair specifications and procedures. Reassembles engines and other systems, and adjusts, tests, and reinstalls in vehicles and equipment as necessary. Makes adjustments and repairs to electrical and suspension systems. May install pistons, sleeves, rings, bearings, rods, crankshafts, timing gears, and rocker arms. May be required to perform fuel injection equipment repair, overhaul, rebuild, and calibration duties utilizing a variety of complex test and calibration equipment. Independently performs repairs and maintenance functions in remote locations that can be accomplished by removing, cleaning, reinstalling, or replacing defective parts of components and systems such as injectors, leaking wheel cylinders, corroded mufflers, fuel tanks, brake cylinders and worn brake shoes, voltage regulators, generators, injector pumps, and fuel pumps. Provides technical guidance and specialized team leadership to lower grade employees within the team. Assists lower grade mechanics in performing major repair work. May provide Field and limited Sustainment maintenance at unit locations as part of a “contact team.” Recovers and evacuates inoperable vehicles from the unit location of breakdown. May assist higher graded mechanics in repairing a variety of interconnected systems such as electrical, air and hydraulic systems, complex state of the art electrical and electronic systems that use specialized diagnostic equipment to identify problems, complex fuel injection systems and other similar complex systems. Conducts readiness and repair inspections on vehicles and associated equipment supported by the activity. Performs operational inspections and ensures vehicles and equipment are properly serviced, including brake adjustments, replacing hydraulic fluids, greasing, cleaning, etc., and performs other preventive maintenance operations as required. Inspects supported equipment prior to use during Inactive Duty Training (IDT) and Annual Training (AT), to ensure that it is functioning properly. May inspect in-process repair work of lower graded repairer to ensure equipment is being repaired in accordance with pertinent requirements. May serve as a commodity inspector during Command Maintenance Management evaluations (COMET) or as a member of a Maintenance Assistance Instruction Team (MAIT). Instructs operator/crew in the maintenance of equipment and provides technical advice and assistance to supported units when requested. May maintain and repair electronics communication equipment by removing and replacing components and elements. Equipment includes such items as radios, field telephones, amplifiers, switchboards, recorders, intercoms. Assists in the maintenance of production reports and records, and makes recommendations to the supervisor. Plans, organizes, and performs technical analysis's as required or assigned. Makes recommendations to the supervisor as to adjustments necessary to effectively, efficiently and economically accomplish the work and maximize production. Performs other duties as assigned.