This instructor-led course is designed to provide participants who have Komatsu engine experience, the necessary technical training for understanding the function, maintenance, service, repair & troubleshooting of the 6D107,6D114, 6D125,& 6D140 Tier 4 final & interim engines. This course is developed to carry the participant through both Tier 4 engine systems, starting with the Tier 4 interim engines. This course will cover changes to the Base Engines, Solutions by Horsepower Rating, the Variable Geometry Turbocharger, Diesel Particulate Filter, & all the related sensors for Tier 4 interim & final engines. The DEF System including fluid properties, tank & cooling system, tank sensor, pump & injector modules, thawing & freeze prevention logic will be covered as well. Hands-on training will take place using a Tier 4 Final & Interim Machines. On-board diagnostic testing, creation of Inducement fault codes.