We use two steps: 1. Insert a medical-grade endoscope through the spark plug hole to visually inspect cylinder wall scratches and carbon buildup on the piston top; 2. Extract an engine oil sample to check for large metal debris or emulsification (caused by coolant leakage).

We mainly collaborate with professional organizations certified by China's national CMA (Certification of Inspection and Testing Institutions). If you need the highest level of international endorsement, we can arrange for independent inspection agencies like SGS or TÜV to conduct Pre-Shipment Inspections (PSI) before loading at the port.

No hidden fees. The total amount on the FOB/CIF invoice is the final amount. We rely on professional supply chain operations to earn a reasonable margin and do not allow any sales personnel to privately request kickbacks or service fees from you.