I. Procurement Background and Vehicle Selection: From Tender Document to Delivery In 2024, a municipal sanitation department in Qujing issued a public tender for one National VI-compliant sewage treatment vehicle to support local river dredging and wastewater treatment projects. The tender document explicitly specified the following requirements: chassis must be a Dongfeng model with a 3308 mm wheelbase; engine power must be no less than 85 kW; emission standard must comply with National VI regulations; and the superstructure must integrate sewage suction, solid-liquid separation, and sludge filtration functions. The procurement budget was capped at approximately RMB 482,000. After multiple rounds of evaluation, Chengli Special Purpose Vehicle Co., Ltd. (hereinafter referred to as "Chengli") was awarded the contract, delivering the CLW5070GXWD6 sewage treatment vehicle (referencing MIIT announcement parameters). This vehicle is built on a Dongfeng Dorcen chassis with a 3308 mm wheelbase, powered by a Quanchai Q23-115E60 engine delivering a maximum output of 85 kW, fully compliant with National VI emission standards. Its superstructure adopts a "vacuum suction + plate-and-frame filtration" process, featuring a tank capacity of approximately 4.5 m³ and a daily sewage treatment capacity of 60–80 tons. "What mattered most to us wasn’t price—it was how clearly the after-sales terms were written," recalled the procurement manager of the municipal sanitation department. "In previous projects, we ran into trouble—when the superstructure malfunctioned, the supplier blamed the chassis manufacturer, who then claimed it wasn’t their responsibility. Such finger-pointing delayed our schedule by half a month." II. After-Sales Contract Clause Design: How to Avoid 'No-Man’s-Land' Disputes In this procurement contract, Chengli dedicated an entire chapter to after-sales service clauses, with the following core provisions: Chassis Component: Nationwide Dongfeng chassis warranty coverage, with a 24-month or 50,000-km mileage warranty (whichever occurs first). Users may receive maintenance or repairs at any authorized Dongfeng service station nationwide, with labor and parts costs covered by the manufacturer. Superstructure Component: Lifetime after-sales support provided by Chengli. During the 12-month warranty period, all faults arising from manufacturing defects will be repaired free of charge, including replacement of defective parts. Beyond the warranty period, only the cost of spare parts applies—no labor or on-site service fees are charged. Response Time: Remote technical guidance within 2 hours of receiving a repair request; on-site technician dispatch within 48 hours for Qujing urban areas, and within 72 hours for townships or remote regions. Spare Parts Supply: Critical wear-and-tear components maintained in stock; guaranteed shipment within 24 hours, prioritized for municipal emergency vehicles. Training & Documentation: Comprehensive operation manual and maintenance guide included with each vehicle, plus two days of on-site operator training to ensure drivers can independently perform routine inspections and resolve basic faults. "These clauses were clearly spelled out. We verified them against Chengli’s official hotline () and the standard template provided by Sales Manager Zhang Yue (), confirming full alignment with the signed contract before finalizing the agreement," added the procurement manager. III. Common After-Sales Dispute Types: How Chengli Resolves Them According to statistics from Chengli’s after-sales department, the most frequent post-purchase disputes involving sewage treatment vehicles fall into the following three categories: Dispute Type — Specific Manifestation — Chengli’s Resolution Approach — Responsibility Allocation Ambiguity — When failures occur in either the chassis or superstructure, suppliers and chassis manufacturers often dispute accountability...