Engine lubricants play an important role in lubrication, cooling, cleaning, and rust prevention for vehicles, construction machinery, ships, airplanes, and other equipment with internal combustion or turbine engines. As the lubricant deteriorates through use, its performance will decline and the inside of the engine can wear, leading to a decrease in service life and potential malfunction.
Lubricants deteriorate due to decomposition and chemical changes of oil components and additives caused by physical and thermal stresses, as well as contamination by metal wear particles and incorporated fuel. Therefore, it is recommended to analyze the lubricant throughout its lifespan to assess its quality, utility, and remaining service life. These analyses can be accomplished with a number of instruments.

Typical causes of engine lubricant deterioration diagram

Typical causes of engine lubricant deterioration

Examples of ASTM Lubricant Analysis Methods

Analysis items (Elements) Needed system Standards
Deterioration Oxidation FT-IR ASTM E2412
Nitration
Sulfate by-products
Contamination Water FT-IR ASTM E2412
Soot
Gasoline GC ASTM D3525
ASTM D7593
FT-IR ASTM E2412
Diesel GC ASTM D3525
ASTM D7593
FT-IR ASTM E2412
Coolant (B, Na, K) ICP-AES ASTM D5185
FT-IR ASTM E2412
Antifreeze (Na) ICP-AES ASTM D5185
Dust (Si)
Seal materials (Si)
Wear Metals (Al, Fe, Cu, Cr, Ni, Zn, etc.) ICP-AES ASTM D5185
Additives Anti-oxidant (Zn, Cu, B) ICP-AES ASTM D4951
FT-IR ASTM E2412
Anti-wear agents (B, Cu, K, S, Zn, etc.) ICP-AES ASTM D4951
FT-IR ASTM E2412
Detergent inhibitors (Ba, Mg, Ca, etc.) ICP-AES ASTM D4951
Corrosion inhibitors (Ba, Zn)
Anti-rusting agents (K, Ba)
Friction modifier additives (Mo)

Lubricant Deterioration Analysis Using Compact FT-IR

FTIR Spectrophotometer for Lubricant Deterioration Analysis

FTIR Spectrophotometer

Applicable Method

Condition Monitoring of Lubricant oil (ASTM E2412/D7418/D7414/D7415/D7412)

Analysis of Additive Elements, Wear Metals, and Contaminants in Used Lubricants using ICP-AES