Mono Grade Diesel Engine Oil

Monograde, mono-grade, or straight weight simply refers to the single requirement that these engine oils cover according to the SAE J300 classification system: that is, these oils - in contrast to multigrade oils - may not use a viscosity index improver (an additive that helps oil to maintain its desired level of thickness). That renders these oils less versatile and instead require different weights and viscosities depending on the application and time of year. If you have any questions regarding API performance categories or monograde vs. multigrade oils, please give us a call at 1-855-899-7467.