The John Deere M87879 is an authentic OEM main bearing cap bolt, crucial for securely fastening the main bearing caps within the engine block. This high-quality bolt ensures the proper alignment and function of the crankshaft, contributing to the overall durability and performance of the engine. It is specifically designed for a wide range of John Deere agricultural equipment, including numerous tractor models such as the 1020, 2030, 2140, and 3350 series, among others, providing a precise fit and reliable operation.