This research addresses by evaluating the individual and synergistic effects of zinc oxide (ZnO) and silicon dioxide (SiO₂) nanoparticles when incorporated into (10W-30) and (10W-40) commercial oils to upgrade their performance. The nanomaterials were synthesized via the sol–gel technique, yielding high-purity particles (99.9% for ZnO and 98.0% for SiO₂) with well-defined parameters. The diameters and surface areas of ZnO and SiO₂ particles were 55–95 nm and 40–60 nm, 65 m²/g and 160–200 m²/g, respectively. In terms of attempting to reach the best concentration, 1.0 % by weight concentration was used of each nanomaterial (after testing different ratios). A two-stage preparation procedure was used to obtain a stable nano-lubricant at room temperature. Firstly, a magnetic stirrer was used with the addition of oleic acid. Secondly, a high-speed mixer was used. The results confirmed a noticeable enhancement in the physical properties of the nano-lubricants. The viscosity index was recorded to be improved from 118.2 to 120.1 and 121.8 for ZnO/10W-30 oil and SiO₂/10W-30 oil, respectively. For ZnO/10W-40 and SiO₂/10W-40, the viscosity index rose from 117.2 to 122.5 and 119.3, respectively. For the hybrid formulation, the mix of 0.75 wt.% ZnO/0.25 wt.% SiO₂ was used (the best hybrid concentration yielded 1.0 % after experiencing different ratios) with both oil grades, 10W-30 and 10W-40, the viscosity index was 122 and 119, respectively. It was concluded that nanoadditives could be the solution to the shortcomings in the performance of commercial oils by raising the viscosity index, flash point, and reducing the pour point.