How often should the oil in a school bus be changed to maintain engine health?

Answer: B — Every 3,000 to 5,000 miles

Changing the oil in a school bus every 3,000 to 5,000 miles is widely recommended to maintain optimal engine health. Regular oil changes are crucial because the oil lubricates the engine's moving parts, reducing friction and helping to prevent damage from wear and tear. Over time, engine oil can become contaminated with dirt, debris, and combustion byproducts, which can lead to sludge buildup and reduce its effectiveness. Sticking to this mileage range ensures that the oil remains in good condition, providing adequate protection for the engine and promoting better fuel efficiency. For many diesel engines, which are common in school buses, more frequent oil changes are often advised to cope with the higher levels of soot and contaminants that can accumulate. While some modern engines may be capable of extending oil change intervals, sticking to the 3,000 to 5,000-mile guideline is a safe practice that aligns with many manufacturers' recommendations, especially for school buses that are typically subjected to rigorous operating conditions.