Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. The Caterpillar 797B is an off-highway, ultra class, two-axle, mechanical powertrain haul truck developed and manufactured by Caterpillar Inc. in the United States specifically for high production mining and heavy-duty construction applications world-wide. The 797B is the second generation of the 797 series. The 797B was introduced to the public in spring of 2002 and first entered service with a customer in October, 2002. The 797B remained in production until December, 2009 when Caterpillar started full production of the 797B''s successor, the 797F. While it was in production, the 797B was Caterpillar''s largest, highest payload capacity haul truck model. Compared to the first generation 797, the 797B has a larger payload capacity and a more powerful engine. These changes allowed Caterpillar to meet mine operators'' needs to increase operational efficiency and reduce costs by increasing the amount of material hauled per trip.