Buying a used engine can save vehicle owners thousands of dollars compared to purchasing a brand-new engine. However, many buyers feel confused when they see terms like Grade A engine, low-mileage engine, or tested used engine. These grading terms are commonly used by auto recyclers and engine suppliers in the United States, but not everyone understands what they actually mean. https://car-partsusa.com/how-used-engine-quality-is-graded-what-it-really-means/