Examples of test setups include "Ball-on-cylinder" and "Ball-on-three-discs" tests.
In a modern diesel engine, the fuel is part of the engine lubrication process. Diesel fuel naturally contains sulfur compounds that provide good lubricity, but because of regulations in many countries (such as the US and the EU) sulfur must be removed. Reformulated diesel fuel has a lower lubricity and requires lubricity improving additives to prevent excessive engine wear.
Treating fuel with additional lubricity enhancers: taking the mystery out of lubricity.(MARKETING & SUPPLY)(American Society of Testing Materials )
Mar 01, 2010; BEFORE THE ADVENT OF ULSD (ULTRA LOW SULFUR Diesel), defined as diesel fuel having a maximum 15 ppm sulfur content, the...