This service manual provides information for servicing a Stage IIIB crawler dozer with the following models: 1650M Extra Long Track (XLT) Bulldozer (BD) Blade, 1650M XLT Power Angle Tilt (PAT) Blade, and 1650M Wide Track (WT)/Low Ground Pressure (LGP) PAT Blade with PIN numbers NGC107000 and above. The manual contains sections on the engine, hydrostatic drive, brakes and controls, hydraulic systems, tracks and suspension, climate control, electrical systems, blade and arm, tools, cab, bodywork and decals.