How many miles is too many on a diesel truck?

The acceptable mileage for a diesel truck can vary significantly based on factors like maintenance, usage, and model. Generally, a diesel truck can last well over 200,000 miles if properly maintained, with some models exceeding 500,000 miles. However, if a truck has over 300,000 miles and shows signs of wear or neglect, it may be considered too many miles for a reliable purchase. Ultimately, it's essential to assess the truck's service history and overall condition rather than just focusing on the mileage.