Government Procurement Case and Bid-Winning Solution Analysis of the CN6 Dongfeng 3308 mm Wheelbase Sewage Treatment Vehicle in Daqing City In the municipal sanitation sector, procurement of sewage treatment vehicles must not only meet immediate operational requirements but also consider long-term economic efficiency and reliability. Recently, a municipal sanitation department in Daqing conducted a public tender for a batch of CN6 Dongfeng 3308 mm wheelbase sewage treatment vehicles, with Chengli Special Purpose Vehicle Co., Ltd. ultimately delivering several customized units. This article provides an in-depth analysis of this case from perspectives including service life, total cost of ownership (TCO), major overhaul intervals, and vehicle depreciation characteristics—offering objective, quantifiable reference data for relevant procurement entities. Project Background and Procurement Requirements The procuring entity for this project was the Urban Management Bureau of a district in Daqing City, primarily requiring vehicles for urban sewer network cleaning, emergency sewage treatment, and rain-season drainage operations. According to publicly released tender information, the project specified a CN6 emission-compliant chassis with a 3308 mm wheelbase; the superstructure was required to feature sewage suction, solid-liquid separation, temporary storage, and hydraulic self-unloading capabilities. The budget cap was approximately RMB 667,000 per unit, with two units procured. Chengli Special Purpose Vehicle’s proposed solution was based on the Dongfeng 3308 mm wheelbase chassis, referencing the CLW5070GSSD6 series (CN6 official announcement). The superstructure employed a stainless-steel tank and hydraulic self-unloading system, with an effective capacity of 8 m³. While fully complying with all announced technical specifications, this solution emphasized enhanced suction performance of the sewage pump and superior tank corrosion resistance—specifically engineered to withstand Daqing’s harsh winter temperatures and highly corrosive sewage environments. Service Life and Total Cost of Ownership (TCO) Analysis For high-intensity operation vehicles such as sewage treatment trucks, the core metric guiding procurement decisions is the “Total Cost of Ownership over the service life.” Below is a comparative TCO analysis across three operational periods—5 years, 8 years, and 10 years—based on industry experience and Chengli vehicle characteristics: Cost Item 5-Year Cycle 8-Year Cycle 10-Year Cycle Purchase Cost (per unit) Approx. RMB 280,000–320,000 Approx. RMB 280,000–320,000 Approx. RMB 280,000–320,000 Annual Fuel/Electricity Cost Approx. RMB 30,000 Approx. RMB 28,000 Approx. RMB 25,000 Annual Maintenance & Servicing Approx. RMB 15,000 Approx. RMB 20,000 Approx. RMB 25,000 Major Overhaul Cost (one-time) Approx. RMB 40,000 Approx. RMB 60,000 Approx. RMB 80,000 Residual Value Recovery Approx. RMB 120,000 Approx. RMB 80,000 Approx. RMB 40,000 Total Cost of Ownership (per unit) Approx. RMB 320,000–360,000 Approx. RMB 400,000–450,000 Approx. RMB 480,000–540,000 Note: The above figures are derived from publicly available tender documents and industry benchmarks; actual costs may vary depending on usage intensity, road conditions, and maintenance standards. Chengli vehicles benefit from Dongfeng chassis nationwide warranty coverage and offer 48-hour direct delivery of critical spare parts (e.g., sewage pumps, seals), reducing annual maintenance costs by approximately 10%–15%. Major Overhaul Costs and Intervals: Industry Patterns and Chengli’s Advantages The high-pressure sewage pump, hydraulic system, and tank anti-corrosion coating constitute the most critical wear-prone components in sewage treatment vehicles. Based on industry experience under normal operating conditions: First Major Overhaul Interval: Typically occurs at 4–5 years (approximately 4,000–5,000 operating hours), primarily involving replacement of the sewage pump, inspecti