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Purpose: This study aims to prevent the sharp decline in the load-carrying capacity of lubricating oil film under harsh conditions of abrupt changes in friction interface temperature, which is a major challenge in lubrication technology. Design/methodology/approach: In this paper, we synthesized a series of silver pyrazole methylpyridine complexes containing a high metal concentration and minimal supporting organic ligands (complex 1 [Ag(LMe)]2(BF4)2, complex 2 [Ag(Li-Pr)n](BF4)n and complex 3 [Ag(LMe)(NO3)]2). The thermal decompose behavior of as-prepared silver complex was investigated by thermogravimetric analysis and X-ray photoelectron spectrometry (XPS). Four-ball friction testers were used to evaluate the friction and wear properties of lubricating oil in the temperature ranges associated with the operation of modern heavy machinery. Findings: The complex decomposed silver particles at high-temperature, which could fill the pits on the friction surface, change the wear form of the friction pair and reduce the roughness of the friction surface. Reduction in both friction coefficients and wear scar diameters was obtained by adding silver complexes in oil. The lubricating oil, with the additive content of 1.5 Wt.%, has the best tribological performance, moreover, the lubricating performance of the silver complexes in oil were correlated with their concentration and thermal decomposed temperatures, respectively. Originality/value: As a result, a series of silver pyrazole methylpyridine complexes as oil additives can support friction and wear reduction under abrupt high-temperature conditions are intended to be a controllable backup lubricant additive. [ABSTRACT FROM AUTHOR]