The CNH NEF TIER III Series engines represent a robust line of diesel powerplants designed for demanding applications. Featuring a 4.5-liter, 4-stroke, in-line cylinder configuration, these engines incorporate advanced technologies such as supercharging and intercooling, alongside a common rail and electro-injector fuel system. Emission control is managed through EGR systems, adhering to Tier III standards. The engineering emphasizes reliability and efficient operation, making them suitable for a wide range of industrial and agricultural equipment. This Workshop Service Repair Manual provides comprehensive guidance for the maintenance and repair of the CNH NEF TIER III Series engines. It covers essential procedures including engine disassembly and assembly, detailed component overhauls for critical parts like the cylinder head, pistons, and shafts, and system-specific maintenance for fuel, lubrication, and cooling. The manual also includes diagnostic information, fault codes, special tool requirements, and torque specifications, empowering owners, technicians, and mechanics to ensure optimal performance and longevity of their equipment.