Government procurement case of the Sinotruk 24 m³ sludge self-loading transport truck in Dalian: Anti-freezing solution and bid-winning analysis. In Dalian—a northern coastal city—municipal sanitation departments face three major challenges when operating sludge self-loading transport trucks during winter: low temperatures, salt fog corrosion, and slippery road conditions. In winter 2025, a municipal sanitation department urgently launched a procurement project for 24 m³ sludge self-loading transport trucks due to frequent operational failures—including difficult cold starts and hydraulic system leaks—in aging equipment. This article uses this case as a reference, offering a detailed analysis—from pain-point identification and needs assessment to solution matching and delivery evaluation—of how Chengli Special Purpose Vehicles delivered a high-cost-performance solution based on Sinotruk chassis, specifically tailored for Dalian’s environmental conditions. I. Pain Points of Aging Equipment: The 'Three Major Obstacles' to Winter Operations The municipal sanitation department operated five sludge self-dumping trucks, all over eight years old, primarily responsible for transporting sludge from municipal wastewater treatment plants to landfills. Internal records indicate that equipment failure rates reached as high as 40% between November 2024 and February 2025, directly reducing transportation efficiency by 30%. The core pain points were concentrated in the following three areas: 1. Difficulty in Cold-Weather Starting: Dalian’s winter minimum temperatures can drop to -15°C to -20°C. Aging vehicles suffered frequent 'no-start' incidents due to battery degradation and excessively viscous engine oil. In December 2024, one vehicle failed to start, causing sludge to accumulate at the plant site; external vehicles had to be urgently deployed, increasing single-incident costs by approximately RMB 8,000. 2. Poor Low-Temperature Hydraulic System Stability: At low temperatures, hydraulic fluid viscosity increases sharply, resulting in slow body lifting and seal shrinkage-induced leakage. In January 2025, a hydraulic hose burst mid-unloading on a main urban road, spilling sludge and triggering public complaints—resulting in fines and cleanup costs totaling approximately RMB 12,000. 3. Absence of Winter-Specific Maintenance Protocols: The original manufacturer provided no specialized maintenance guidance for low-temperature environments. Improper replacement intervals for antifreeze and engine oil accelerated engine wear. Total winter 2024 maintenance expenses amounted to approximately RMB 180,000—exceeding the residual value of the vehicles. These pain points prompted the department to initiate an emergency procurement process in February 2025, specifying strict requirements for new vehicles: engine cold-start capability at temperatures below -20°C; hydraulic system stability under sub-zero conditions (continuous operation for 8 hours); and a comprehensive winter maintenance program. II. New Requirements Assessment: From 'Purchasing One Vehicle' to 'Procuring an Integrated Solution' The department issued its procurement tender in March 2025, with a budget cap of approximately RMB 333,000 (based on publicly available tender information). According to policy guidelines and FAQs in our knowledge base, Dalian imposes additional requirements for sludge self-loading trucks: chassis must be salt-fog corrosion-resistant; cargo bodies must be fully sealed and leak-proof; and heating/thermal insulation systems must be installed. During the evaluation phase, the procurement team assessed three manufacturers: a local upfitter, a northern domestic brand, and Chengli Special Purpose Vehicles. Chengli stood out due to its proven expertise in modifying Dongfeng and Sinotruk chassis, along with its after-sales commitment—'nationwide Dongfeng chassis warranty + lifetime upper-body structure service from Chengli.' Notably, Chengli’s track record—documen