What are the main contents of the secondary maintenance for vehicles?

[MacFaith]

The purpose of secondary vehicle maintenance is primarily inspection and adjustment, with objectives and items as follows: Items: Replace engine oil and oil filter, check coolant level and quality, check power steering fluid level and quality, check brake fluid level and quality, replace the oil in the oil pan, and clean the oil pan, oil pump, and oil strainer with kerosene, inspect and adjust valve clearance, tighten cylinder head, intake and exhaust manifold, and muffler bolts. Objectives: Mainly to improve the working conditions of various components, reduce wear, eliminate hidden dangers, lower costs, avoid premature damage, and maintain the vehicle in good working condition.