Which statement about ashless dispersant oil is true?

Which statement about ashless dispersant oil is true?

• A. It contains ash-forming additives.
• B. It disperses contaminants and contains no ash-forming additives.
• C. It is synthetic oil.
• D. It is designed for automotive engines.

Answer: (B)

Ashless dispersant oil is formulated to keep contaminants suspended in the oil so they can be carried away or burned off, preventing sludge and varnish deposits. The “ashless” part means it does not include ash-forming additives that would leave solid residues after combustion. So it’s designed to disperse contaminants without leaving ash-forming ash behind. It isn’t defined by being synthetic oil—base stock can be mineral or synthetic—and its use isn’t limited to automotive engines; in aviation contexts the emphasis is on keeping deposits from forming in engines. That’s why the true statement is that it disperses contaminants and contains no ash-forming additives.

Ashless dispersant oil is formulated to keep contaminants suspended in the oil so they can be carried away or burned off, preventing sludge and varnish deposits. The “ashless” part means it does not include ash-forming additives that would leave solid residues after combustion. So it’s designed to disperse contaminants without leaving ash-forming ash behind. It isn’t defined by being synthetic oil—base stock can be mineral or synthetic—and its use isn’t limited to automotive engines; in aviation contexts the emphasis is on keeping deposits from forming in engines. That’s why the true statement is that it disperses contaminants and contains no ash-forming additives.