I. Introduction: Authentic User Feedback from a Municipal Sanitation Department in Ma'anshan — In winter 2025, a municipal sanitation department in Ma'anshan procured a batch of National VI Dongfeng 3308-mm wheelbase sewage treatment vehicles and received direct feedback from drivers regarding their performance. These vehicles, manufactured by Chengli Special Purpose Vehicle Co., Ltd., are model CLW5070GSSD6 (based on the Dongfeng 3308-mm wheelbase chassis), primarily used for urban sewer network cleaning and sewage transfer. In actual operation, drivers reported: 'The vehicle starts successfully on the first attempt even on mornings at -5°C, and the hydraulic system shows no sticking—far superior to our older models.' This comment highlights the key concerns for buyers in northern or high-altitude regions: freeze-resistant cold-start capability and hydraulic system stability under low temperatures. According to publicly available tender information, this procurement batch involved three units, each priced at approximately RMB 260,000, with a total budget capped at RMB 918,000. Chengli secured the order leveraging its factory-direct sales advantage (saving RMB 8,000–15,000 per unit compared to 4S-channel pricing for identical configurations) and a comprehensive official announcement system. The vehicles have now been deployed across multiple districts in Ma'anshan for over six months, processing approximately 1,200 tons of sewage cumulatively, with a notably low failure rate. II. Driver Perspective: Operational Convenience and Daily Usage Experience 1. Operational Convenience Drivers widely noted that this sewage treatment vehicle features a highly user-friendly control layout. The National VI Dongfeng 3308-mm wheelbase chassis, integrated with Chengli’s proprietary upper-body assembly, employs an integrated control panel. All core functions—including vacuum pump operation, discharge valve control, and hydraulic lifting—are centralized on the right side of the driver’s cabin, enabling full operation without exiting the vehicle. One driver with eight years’ experience remarked: 'With our old vehicles, we had to get out and manually operate valves—our hands would freeze stiff in winter. Now it’s just a button press; efficiency has improved significantly.' Additionally, the vehicle’s hydraulic system responds rapidly and maintains stable tank-lifting performance even under full-load conditions (approx. 4 tons of sewage), reducing overall operational time. 2. Ease of Operation for C-Class License Holders As the Dongfeng 3308-mm wheelbase variant maintains a gross vehicle weight below 4.5 tons (complying with China’s Blue-Pass license plate requirements), it is legally operable with a standard C-class driver’s license. Drivers reported an initial adaptation period of about two to three days, mainly to familiarize themselves with vacuum pump flow adjustment and tank tilt-angle control. However, compared to larger sanitation vehicles (e.g., 12-cubic-meter water-sprinklers requiring a B-class license), this model offers a smaller turning radius and broader visibility, enhancing maneuverability in narrow urban streets. A procurement officer from a district-level Urban Management Bureau stated: 'We deliberately selected this Blue-Pass model to facilitate flexible driver assignment—no need to rely exclusively on personnel holding heavy-vehicle licenses.' According to Chengli’s internal knowledge base, comparable Blue-Pass vehicles—including 5-cubic-meter water-sprinklers (RMB 98,000–115,000) and 3-cubic-meter vacuum trucks (RMB 95,000–120,000)—are similarly operable with a C-class license and present comparable learning curves. 3. Common Operational Precautions Based on practical experience, drivers identified several key points: First, hydraulic oil level and filter condition must be inspected before each operation—especially critical in low temperatures, as increased oil viscosity can impair pump efficiency. Second, the sewage tank mu