Case Study and Bid-Winning Solution Analysis of the National VI Dongfeng 3308 mm Wheelbase Sewage Treatment Vehicle Procurement in Mianyang City. In the municipal sanitation sector, sewage treatment vehicles—due to their specialized functional requirements—are often challenging procurement items. At the end of 2024, the Urban Management Bureau of a district in Mianyang City, Sichuan Province, procured four National VI Dongfeng 3308 mm wheelbase sewage treatment vehicles via public tender, with final delivery completed by Chengli Special Purpose Vehicle Co., Ltd. This article interprets the project requirements, winning bid solution, and vehicle highlights based on publicly available tender information, offering reference for similar procurement projects. I. Project Basic Information. According to publicly released tender information, a district in Mianyang City procured four sewage treatment vehicles to enhance local sewage treatment capacity, with a total budget capped at approximately RMB 2.248 million. Core project requirements included: Chassis Requirements: National VI emission standard; Dongfeng chassis with 3308 mm wheelbase, suitable for urban and rural road operations; Functional Requirements: Capable of sewage suction, solid-liquid separation, and reclaimed water reuse, with a minimum single-cycle treatment capacity of 8 cubic meters; Operating Environment: Primarily intended for urban sewage pipeline maintenance, septic tank cleaning, and emergency response; Delivery Timeline: Full delivery to be completed within 30 days after contract signing. Chengli Special Purpose Vehicle Co., Ltd. stood out among multiple suppliers thanks to its mature, MIIT-certified vehicle models (e.g., CLW5070GSSD6 and similar variants) and lifetime after-sales service commitment. All four vehicles have now been deployed and are operational in Mianyang. II. Analysis of Chengli’s Bid-Winning Factors. Based on standard procurement practices, Chengli secured this contract primarily due to the following advantages: Comprehensive MIIT Announcements Enabling Nationwide Registration: All Chengli vehicle models are listed in the MIIT’s official vehicle announcement database; the specific chassis model used in the Mianyang project had already been pre-registered, eliminating potential registration or licensing complications. Factory-Direct Sales Ensuring Cost Control: As a local manufacturer based in Suizhou, Chengli eliminates intermediaries—delivering the same configuration at RMB 8,000–15,000 lower cost compared to 4S dealership channels, a decisive advantage under tight budget constraints. Lifetime After-Sales Support for Superstructure: Recognizing the demanding operating conditions of sewage treatment vehicles, Chengli provides lifetime after-sales service for the superstructure, while the chassis is covered under Dongfeng’s nationwide warranty network—significantly reducing long-term operation and maintenance risks. Reliable Delivery Capability: Standard models are typically delivered within 7–15 days; although the Mianyang project required delivery within 30 days, Chengli’s zero-inventory dispatch model ensured on-time fulfillment. Additionally, Chengli has previously served over 500 municipal sanitation clients—including prior deliveries of four cleaning/suction-sewer trucks to Sichuan municipal authorities—accumulating valuable regional experience that enables rapid, responsive customer support. III. Key Technical Features of the Delivered Vehicle Model. The delivered vehicles are built upon the Dongfeng 3308 mm wheelbase chassis, equipped with a National VI-compliant engine and integrated with Chengli’s proprietary superstructure. Key technical features include: High-Efficiency Solid-Liquid Separation System: Utilizes cyclonic separation technology to remove over 80% of solid contaminants (e.g., fecal matter, silt) from wastewater, achieving a reclaimed water reuse rate of approximately 60%–70%, thereby minimizing environmental discharge;