I. Case Background: Winter Procurement Challenges Faced by Harbin Municipal Sanitation Department In winter 2025, a municipal sanitation department in Harbin planned to procure a batch of blue license plate sewage treatment vehicles for routine cleaning and emergency pumping of urban street drainage networks and septic tanks. The project budget was capped at approximately RMB 245,000, with requirements including: operability by C1 driver’s license (blue plate compliance), China VI emission standard, and capability to withstand Harbin’s winter temperatures as low as -30°C. During preliminary research, the procuring party found that certain models on the market encountered difficulties such as cold-start failure, hydraulic fluid solidification, and pipeline freezing under low-temperature conditions—directly impacting operational efficiency. After multiple rounds of tendering and on-site inspections, the department ultimately selected Chengli Special Purpose Vehicle Co., Ltd. (hereinafter referred to as “Chengli”) for its Dongfeng D6 chassis-based blue license plate sewage treatment vehicle, referencing model series CLW5070GSSD6 per official announcement parameters. This batch of vehicles has now been delivered and commissioned; customer feedback confirms stable operation under extreme weather conditions, and the winter maintenance plan has also received positive recognition. II. Core Requirement Analysis: Why Winter Performance Is Critical Harbin’s winter temperatures plummet to -30°C to -40°C, imposing stringent demands on special-purpose vehicles. The procuring party explicitly specified the following key technical criteria in its tender documents: • Cold-Start Resistance: The vehicle must achieve successful ignition in a single attempt at -25°C ambient temperature, equipped with either a preheating device or low-temperature battery. • Low-Temperature Hydraulic Stability: Hydraulic fluid must remain non-solidified at sub-zero temperatures; pipeline sealing components must retain flexibility and resist embrittlement to ensure continuous, reliable suction and discharge operations. • Winter Maintenance Plan: The supplier must provide a comprehensive winter maintenance guide, covering antifreeze replacement intervals, recommended hydraulic oil specifications, and cold-start procedures for the chassis. • Blue License Plate Compliance: Gross vehicle weight must not exceed 4.5 tons, enabling operation with a C1 driver’s license and nationwide registration, annual inspection, and commercial operation. In its tender proposal, Chengli addressed these requirements by offering the Dongfeng D6 chassis (equipped with a China VI diesel engine, optionally fitted with fuel heater or electric glow plugs) paired with a customized upper assembly (using low-temperature hydraulic oil, insulated piping, and freeze-resistant tank coating), along with a complimentary “Harbin Region Winter Operation & Maintenance Manual for Special-Purpose Vehicles.” III. Competitive Benchmarking: Chengli Dongfeng D6 vs. Market Alternatives To support the procuring party’s decision-making process, we conducted a comparative analysis across ten core dimensions between Chengli’s Dongfeng D6 and another mainstream blue license plate sewage treatment vehicle on the market (hereinafter “Competitor A,” brand undisclosed). Data sources include publicly available tender information, MIIT official announcement parameters (e.g., CLW5070GSSD6), and verified user field-test feedback. Table 1: Ten-Dimensional Comparative Scorecard — Chengli Dongfeng D6 vs. Competitor A Scoring Dimension Weight Chengli Dongfeng D6 Competitor A Remarks 1. Cold-Start Performance 20% ★★★★★ ★★★☆☆ Chengli features standard fuel heater and low-temperature battery; field tests confirm successful start-up at -30°C. Competitor A only equips standard glow plugs, resulting in lower cold-start success rate. 2. Low-Temperature Hydraulic Stability 20% ★★★★★ ★★★☆☆ Chengli uses low-temperature hydraulic oil (-40