Nanoparticles are particles between 1 and 100 nanometres (nm) in size with a surrounding interfacial layer. One of these famous nanoparticles is nanoboric acid (nBA) additive added in engine oil that drastically lowered friction and wear. This scientifical and experimental work presents the developped new suspended nanoboric acid (nBA) additive added in engine oil and lowered friction and wear in Diesel engine specimens tested in reciprocating tribometer. Proving nBA particles that were in colloidal form in engine oil with Turbiscan Tower Stability Analyzer, the engine oil is tested between piston ring and cylinder liner system in order to investigate their effect on friction and wear under boundary lubricated conditions. Simulation and measurement of friction and wear were conducted using a reciprocating tribometer. Surface analysis was performed using 3D digital optical microscope, Field Emission Scanning Electron Microscope (FESEM)/X-Ray, X-ray photoelectron spectroscopy (XPS) and Atomic Force Microscopy (AFM) from macro to nanoscale. Boron (B) from BA is well detected and mixed with other elements of additives protecting the surface under boundary lubrication conditions. It has found that the friction coefficient is reduced with nBA suspended engine oil and protected the surface mostly on cylinder liner mixing with other additives.