This curriculum guide is part of a series designed to teach students about diesel engines. The materials in this power trains guide apply to both on-road and off-road vehicles and include information about chain and belt drives used in tractors and combines. These instructional materials, containing nine units, are written in terms of student performance using measurable objectives. Each instructional unit includes some or all of the basic components of a unit of instruction: performance objectives, suggested activities for teachers and students, information sheets, assignment sheets, job sheets, visual aids, tests, and answers to the tests. Lessons are illustrated with industry-generated illustrations and units are planned for more than one lesson or class period of instruction. The nine units cover the following topics: introduction to power trains, clutches and flywheels, torque converters and fluid drives, mechanical transmissions, automatic transmissions, drive lines, differentials and final drives, power take-offs, and special drives. (KC)