LO 10-7 Outline lubrication system maintenance and service procedures

Measuring Oil Quality
It is in the best interests of owners and the environment to extend oil change intervals. Owners are motivated to sample engine oil to determine if any oil properties are depleted and whether the oil need not be changed if oil properties are intact. Reduced operating costs are another benefit to oil sampling, as is the fact that important clues about impending engine failures can be detected before a catastrophic failure occurs.

From an environmental viewpoint, extending oil change intervals reduces environmental waste. According to the EPA, of the 1 billion gallons of engine oil consumed every year, about 185 million gallons (700 million L) of used engine oil are disposed of improperly. Likely, the oil is dumped into the ground, tossed into landfills, or poured into sewers. The EPA now encourages vehicle owners to follow the oil change recommendations of the OEMs and not those of the oil change industry. Research has demonstrated that oil changes can be extended by using higher-quality oil and oil analysis for HD diesels.