Oil Analysis - Chemistry

Used as a multifunctional additive in organic antimony compounds such as Antimony diakyl dithiocarbamates (sometimes denoted as SbDTC or ADD).

Known to perform as: anti-scuffing (EW) agents, anti-wear (AW) agents, oxidation inhibitors, copper-lead corrosion inhibitors and rust inhibitors.

Sources: Corrosion Inhibitors, Detergents, Rust Inhibitors. 

Sources: Corrosion Inhibitor additive and Antiwear/Antioxidant additive 

Can indicate coolant leak or grease contamination.

Sources: Detergent/dispersant additive, Alkaline reserve additive for high sulphur fuelled engines. 

Can be from grease contamination.

Sources: Detergent/dispersive additive.

Can also be found as an alloying element in steel.

Sources: Solid/liquid antiwear additive. 

Also used as an alloy in bearing and piston rings.

Sources: Antiwear additives, Corrosion inhibitors, Anti-oxidants additives, 

EP additives.

Sulphur present in fuel or engine oil during combustion can combine with water produced during the combustion process to form sulphuric acid (battery acid) which can cause corrosion to engines. Engine oil lubricants thus have special antacid additives (Base Number) to neutralize the acids (Acid Number).

Sources: Antiwear additive (Zinc dialkly dithiophosphate – ZDDP), Corrosion inhibitors, Anti-oxidants.

Also used for alloying element for bearings, thrust washers and galvanized cases.