The "D-series" refers to a classification of vehicles produced by Volvo, specifically known for their durability and versatility. These trucks and construction vehicles are designed for heavy-duty tasks, making them suitable for various industries, including transportation and construction. The D-series is recognized for its robust performance and reliability in challenging conditions. In addition to their strength, D-series vehicles often feature advanced technology and safety systems, enhancing their operational efficiency. Volvo has focused on sustainability, incorporating eco-friendly engines and fuel-efficient designs in the D-series, aligning with modern environmental standards and regulations.