2003–2006 Yamaha Kodiak 450 4WD Factory Service Manual Set — 467 Pages (P/N LIT-11616-18-35, 5ND-F8197-12)

• 467-page PDF factory set: 373-page YFM450FAR Service Manual, LIT-11616-16-01 / Manual No. 5ND-F8197-10; 24-page YFM450FAS Supplementary Service Manual, LIT-11616-17-25 / 5ND-F8197-11; and 70-page YFM450FAT Supplementary Service Manual, LIT-11616-18-35 / 5ND-F8197-12.
• Exact model-code coverage: YFM450FAR codes 5ND1 and 5ND5; YFM450FAS code 5ND6; and YFM450FAT codes 1D91/1D95 (USA), 1D92/1D96 (Canada), 1D93/1D97 (Europe), and 1D94 (Oceania).
• Engine repair sections cover removal and installation, cylinder-head and valve-train service, cylinder and piston inspection, recoil starter and A.C. magneto work, crankcase separation, crankshaft and oil-pump service, transmission repair, primary and secondary sheaves, centrifugal clutch, middle gear, cooling system, and carburetor repair.
• Four-wheel-drive and final-drive work includes front CV joints, differential and gear-motor checks, differential operation and gear-lash adjustment, FAR rear-axle/final-drive service, and FAT rear CV joints, drive shaft, pinion and bearing replacement, shim positioning, final-drive lash setup, and reassembly.
• Chassis procedures address hydraulic brake bleeding, master-cylinder and caliper repair, steering-stem and bearing-retainer work, tie rods and steering knuckles, front suspension, the FAR swingarm rear suspension, and the FAT rear arms, knuckles, stabilizer, and shock absorbers.
• Electrical diagnosis and reference data cover switch continuity, ignition, starting, charging, lighting, signal, cooling-fan, and 2WD/4WD selecting systems, backed by circuit diagrams, cable-routing layouts, torque tables, fluid specifications, wear limits, clearances, and electrical test values.

Before ordering, match the model code on your ATV’s identification label to the coverage table. The set is intended for professional ATV technicians, independent repair shops, and experienced DIY mechanics.

How the Three Publications Work Together

The YFM450FAT publication is a supplement, and its foreword directs the technician to use it with both the YFM450FAR base manual and the YFM450FAS supplement. All three publications are included in this PDF, so the required base teardown and repair information is already present. The file opens with the FAT update, continues with the full FAR service manual, and ends with the FAS model-specific material. The FAR edition is dated March 2002, the FAS supplement March 2003, and the FAT supplement June 2004.

The model differences are substantial enough that the correct section matters during parts identification and repair. The FAR configuration uses a swingarm/monocross rear suspension and rear-axle arrangement. The FAT update changes the rear chassis to double wishbones with rear knuckles, a stabilizer, rear CV joints, and a revised final-drive assembly. The FAS supplement adds the differential-lock speed-limiter override switch along with updated rear-brake master-cylinder, steering-stem, tie-rod, steering-knuckle, switch-continuity, and signal-system information.

Workshop Coverage and Factory Procedures

The FAR base manual supplies the full repair framework: machine identification, 2WD/4WD/differential-lock operating theory, connection checks, periodic service, engine and drivetrain teardown, chassis repair, electrical fault isolation, and symptom-based troubleshooting. Routine shop procedures include valve-clearance adjustment, ignition-timing and compression checks, coolant service, V-belt inspection, hydraulic brake bleeding, shift-control adjustment, differential and final-drive oil service, toe-in setup, suspension adjustment, and battery and fuse checks.

Removal and disassembly sections use numbered exploded views with job-order charts, followed by inspection, assembly, installation, and final-adjustment information where required. That format is especially useful during cylinder-head and crankcase repair, sheave and clutch work, front differential service, final-drive setup, brake overhaul, and steering or suspension repair.

Yamaha also identifies the required shop tools rather than leaving the technician to improvise. Examples include the crankcase separating tool YU-01135-A / 90890-01135, gear-lash measurement tools YM-01467 / 90890-01467 and YM-01475 / 90890-01475, final-drive bearing-retainer wrench YM-04050 / 90890-04050, and secondary-sheave spring compressor YM-04134 / 90890-04134. The tool list distinguishes US and Canadian numbers from the corresponding 90890-series numbers used in other markets.

Diagrams, Specifications, and Repair Cautions

Diagram coverage includes the coolant flow diagrams, oil flow diagrams, cable-routing layouts, ignition-system circuit diagram, 2WD/4WD selecting-system circuit diagram, and full YFM450FAR, YFM450FAS, and YFM450FAT wiring diagrams. Electrical chapters combine those drawings with component checks and troubleshooting paths instead of presenting wiring alone.

Factory tables supply component-specific torque specifications, approved lubricants and fluids, capacities, inspection limits, gear clearances and lash data, carburetor settings, and electrical resistance or output checks. The supplements replace or add the specifications and procedures that changed, while the base manual remains the reference for unchanged assemblies.

Several shop cautions are model-specific. The final-drive and middle-driven-shaft sections identify bearing retainers with left-hand threads; treating them as conventional right-hand threads can damage the threaded retainer or housing. The 4WD gear-motor procedure also warns that disturbing the indexed shift-fork sliding gear can leave the indicator display out of agreement with the actual 2WD or differential-lock position.

Brake hydraulics, cooling-system pressure testing, engine removal, and drivetrain repair involve safety-critical systems, hot fluids, and heavy assemblies. Follow Yamaha’s warnings and use proper support, lifting, and shop equipment when applying the procedures in this manual set.

Best for professional ATV technicians, independent repair shops, and experienced DIY mechanics who are comfortable working with factory specifications, specialty tools, and electrical test equipment. This is a factory service manual set, not an owner’s manual.