Caterpillar 3P-6787 piston is a Caterpillar piston part for wheel tractor-scraper equipment, listed for models 627, 627B, 637D, and 639D. The 3P-6787 designation identifies the piston used in the engine assembly to convert combustion pressure into linear motion within the cylinder. This replacement part is intended for use in the Caterpillar wheel tractor-scraper powertrain lineup listed above.
