Noise levels are higher, but that sound becomes familiar. After years, you notice even small changes. A slight knock or uneven idle can signal an issue long before it becomes serious. https://www.hubbry.com/u/info_tractorfactory/history/used-tractors-and-the-next-generation-of-farmers/old-tractors-and-honest-work-stories-written-in-grease-and-soil/71987822