In current research, MWCNT-SiO2/oil hybrid nano-lubricant viscosity is experimentally examined. By dispersing 0.05%, 0.1%, 0.2%, 0.4%, 0.8% and 1% volume ofMWCNTs and SiO2 nanoparticle into the engine oil SAE 20W50, the temperature and solid volume fraction consequences were studied. At 40 to 100 degrees C temperature, the viscosities were assessed. The results indicated Newtonian behavior for the hybrid nano-lubricant. Moreover, solid volume fraction augmentation and temperature enhanced the viscosity enhancement of hybrid nano-lubricant. At highest solid volume fraction and temperature, nano-lubricant viscosity was 171% greater compared to pure 20W50. Existedmodels lack the ability to predict the hybrid nano-lubricant viscosity. Thus, a newcorrelation regarding solid volume fraction and temperature was suggested with R-squared of 0.9943. (C) 2017 The Chemical Industry and Engineering Society of China, and Chemical Industry Press. All rights reserved.