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).

Under international practices and our standard CIF/FOB terms, the THC at the port of origin (China) is borne by the seller; all THC and port miscellaneous charges incurred at the destination port during unloading are to be paid by the buyer (consignee) upon local customs clearance and pickup.

Yes. For large B2B government or major fleet procurement projects, to ensure the safety of your deposit, we can issue an advance payment guarantee from one of China's four major state-owned banks, but the buyer must bear the issuance fee.