API & SAE

 

Most of the engine oil can be determined by 2  grades which is

API and SAE.

API is American Petroleum Institute.

This is to determine the engine oil performance. 

SAE is Society Of Automotive Engineer.

It indicates viscosity of an engine oil.

SM is an API grade for Petrol Engine.

The grading of API for petrol engine from higher to lower are as in the following: SM, SL,SJ,SH, SG, SF, SE, SD, SC, SB, SA to no grade.

CI-4 is an API grade for Diesel Engine.

The grading of API for diesel engine from higher to lower are as in the following:

CI-4, CH-4, CG-4, CF-4, CF,CE, CD, CC, CB, CA,  to no grade.