This manual covers the Astra G generation, internally coded as T98, produced for the years 1998, 1999, and 2000. The Astra G represented a significant advancement in compact car offerings, known for its robust engineering, reliable performance, and a variety of body styles including Hatchback, Saloon, Estate/Caravan, Coupe, and Convertible. It was designed to provide a balance of comfort, practicality, and value, making it a popular choice for everyday transportation. The vehicle was equipped with a range of petrol and diesel engines, manual and automatic transmissions, and featured safety systems such as airbags and optional traction control, reflecting the automotive standards of its era. This comprehensive workshop service repair manual provides in-depth, factory-quality information for owners and professional mechanics. It details scheduled maintenance procedures, troubleshooting diagnostic steps for common faults, and complete repair instructions for all major systems, including powertrain, transmission, chassis, and electrical components. The manual includes hundreds of photos, drawings, and integrated wiring diagrams to aid in understanding complex procedures. Its clear, numbered instructions and detailed substeps, along with crucial safety notes, cautions, and warnings, ensure accurate and safe servicing and repair. The manual is presented in English and is fully printable for convenient use in workshop environments.