The Hyster 138579 is a genuine OEM engine bearing set designed for specific Hyster forklift applications. This set features a .040 inch (.040") oversize specification, indicating it is intended for engines requiring larger diameter bearings due to wear or machining. It ensures proper crankshaft support and rotation, critical for engine performance and longevity. Manufactured to Hyster's original equipment standards, this bearing set provides reliable fit and function.