Preface Eternal vigilance in seeking more efficient and economical motor transportation must be everpresent to maintain the industry's enviable growth and stature. The trucking industry is continuallyfaced with spiralingcosts which must be offset by more efficient application of equipment through improved methods and concepts in transportation. The industry must challenge and change these deterrents that limit its scope and potential growththrough better utilization ofthe nation's vastly improved highway systems. New technologies are pressing increased demands on owners@ operators and manufacturers. These demands must ultimately lead to radically improved vehicle standards for safer@ faster and more reliable and efficient transportation. Intelligent Vehicle Highway Systems (IVHS) technology will enhance increased efficiency and improved traffic management@ and the trucking industry will become the first beneficiary. In the future@ environmental concerns will influence these designsand operations. Rising public concern about automotive safety and environmental matters prompts congressional demands for cleaner air and safer more efficient vehicles. The major challenges facing our industry during this decade will be energy and the environment with continued improvement in safety and conservation. Mobile technology will continue to improve and meet the economic requirements of manufacturers@ owners and operators. Motor transport leaders will find this handbook significantly helpful and above all useful in copingwith these problems. Motortruck executives have an unprivileged responsibility to assure that motor vehicles are operated on the highways in a safe and efficient manner so as to reflect credit on both the industry and the operators. This handbook will also serve as a ready reference for motor truck data and solutions to many motor vehicle problems. The trucking industry must create a more favorable image by keeping the general public as well as governmental people better informed on the values of its many services. The fourth edition updates the basic truck engineering data from previous editions and introduces the latest advancements in electronic applications to truck power trains and operations@ assuring optimum performance and economy with a safer and cleaner environment. Useful data from official government tests on anti-lock brakes and traction enhance this edition. Likewise@ environmental concerns are addressed throughthe use of non-polluting vehicles using alternative fuels and electrical energy. This handbook is dedicated to my many friends in the industry who have so generously given oftheir time and specialized knowledge to help make this book more informative@ more authoritative and more readable.