JCB 406, 407, 408 & 409 Wheel Loader Service Manual (P/N 9803/4200)

An official 457-page JCB OEM service manual detailing engine, hydraulic, electrical, and structural specifications for the 400-series wheel loaders (machines with serial numbers starting from 632700).

• Includes the 406, 407, 408, and 409 JCB wheel loader variants, as well as the 409 Telemaster model.
• Official JCB Service publication (P/N 9803/4200, Issue 11).
• Features 47 torque specifications, 16 hydraulic system schematics, and accurate grease-point illustrations.
• Details 11 core mechanical systems, ranging from engine and transmission mechanics to hydraulic steering and electrical architecture.

Component and System Documentation

The manual catalogs procedures across eleven distinct technical groups. The general section outlines fluid capacities, multi-grade oil requirements, and proper anti-freeze ratios. Hydraulics coverage is extensive, providing clear circuit diagrams, pump operation theory, and precise testing parameters for main and auxiliary relief valves. Body and framework sections detail cabin removal, bonded glass glazing, and center pivot overhauls. Engine, transmission, and axle chapters focus heavily on correct assembly, highlighting high-tensile bolt torque requirements for all major joints.

Note that working on heavy machinery hydraulics and pressurized structural components carries inherent physical risks; always ensure you follow factory safety protocols and consult a certified heavy equipment technician before servicing.

Specifications and Data Preview

Accurate technical data is provided for precision assembly and routine maintenance. The manual lists main relief valve operating pressures for each model alongside specific implement circuit pressures. Cylinder ram dimensions, bore diameters, and stroke lengths are tabulated for straightforward component identification. Torque settings for UNF Grade S and Metric 8.8 bolts are explicitly stated to maintain structural integrity and prevent joint failure. Cooling system capacities are clearly mapped out, documenting 12.5 liters for the 406 model and 15.5 liters for the 408 system. Additionally, the primary mounting bolt torque for core machine structures is specified at 47 Nm.