The Mercedes-Benz W123 E-Class, produced for the 1978 model year, represents a pinnacle of mid-size luxury and executive automotive engineering. Renowned for its exceptional build quality, robust durability, and comfortable ride, this chassis competed effectively with other premium European sedans of its era. Its sophisticated design and the brand's heritage of excellence made it a highly sought-after vehicle, celebrated for its longevity and reliable performance across various engine options, including gasoline and diesel variants.

This Factory Service and Repair Manual provides comprehensive, technician-level information for all W123 E-Class models from 1978. It covers all major vehicle systems, including engine mechanicals, fuel and ignition, cooling, lubrication, transmissions, drivetrain, suspension, steering, brakes, and electrical systems. Detailed maintenance procedures, diagnostic guides, repair instructions, and essential specification charts are included, offering definitive, vehicle-specific accuracy to assist owners and professionals in maintaining and repairing this classic Mercedes-Benz.