Here is an internal inspection done by Shell on several diesel engines using various HDEO oils.
Surprizingly, (or unsurprizingly as the case may be), the premuim Chevron Delo 400 didn't do well, even when compared to the less espensive fleet grade Shell Rimula 15w40.
http://www.puradyn.com/downloads/Full_Shell_Motiva_Report.pdf
Surprizingly, (or unsurprizingly as the case may be), the premuim Chevron Delo 400 didn't do well, even when compared to the less espensive fleet grade Shell Rimula 15w40.
http://www.puradyn.com/downloads/Full_Shell_Motiva_Report.pdf