Book excerpt: This updated fourth edition has been completely updated to provide the most current ASE test preparation material for Medium/Heavy Duty Trucks available anywhere. Each book in the series provides valuable preparation for Medium/Heavy Duty Truck Technicians seeking certification in one or more of the ASE Medium/Heavy Duty Truck Technician Certification areas. Readers are afforded scores of opportunities to ascertain their knowledge of critical concepts, through the extensive array of sample problems, ASE-style exams, and competency-specific test questions required for certification by ASE. Refresher materials, helpful test-taking strategies, and thorough explanations round out this comprehensive preparation package.