<!-- @page { margin: 2cm } p { margin-bottom: 0.25cm; direction: ltr; color: #00000a; line-height: 120%; text-align: left; widows: 2; orphans: 2 } p.western { font-family: "Calibri", serif; font-size: 10pt; so-language: en-US } p.cjk { font-family: "SimSun"; font-size: 10pt; so-language: zh-CN } p.ctl { font-family: ; font-size: 10pt; so-language: ar-SA } a:link { so-language: zxx } --> Engine oil lubricates the moving parts of our engine and protects the metallic surface from corrosion. Then, What do oil additives do for our engine? Engine Oil Additives are additional supplements to the base lubricants. They are mainly used for increasing viscosity; enhancing lubricity; and for contaminant control.