SAE TECHNICAL PAPER SERIES The Engineering Society =For Advancing Mobility a and Sea Air andSpace, The Allison HD Transmission Steven F. James Allison Transmission Division General Motors Corporation International Truck & Bus Meeting and Exposition Detroit, MI November 1-4,1993 400 COMMONWEALTH DRIVE, WARRENDALE, PA 15096-0001 U.S.A. Downloaded from SAE International by North Carolina State Univ, Saturday, September 15, 2018The appearance of the ISSN code at the bottom of this page indicates SAE's consent that copies of the paper may be made for personal or internal use of specific clients. The consent is given on the condition, however, that the copier pay a $5.00 per article copy fee through the Copyright Clearance Center, Inc. Operations Center, 27, Congress St., Salem, MA 01970 for copying beyond that permitted by Sections 107 or 108 of the U.S. Copyright Law. This consent does not extend to other kinds of copying such as copying for general distribution, for advertising or promotional purposes, for creating new collective works, or for resale. SAE routinely stocks printed papers for a period of three years following date of publi- cation. Direct your orders to SAE Customer Service Department. To obtain quantity reprint rates, permission to reprint a technical paper or permission to use copyrighted SAE publications in other works, contact the SAE Publications Group. All SAE papers, standards, and sslscred books are abstracted and Indexed in the SAE Global Mob~lrfy Database No part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without prior written permission of the publisher. ISSN 01 48-71 91 Copyright 1993 Society of Automotive Engineers, Inc. Positions and opinions advanced in this paper are those of the author(s) and not nec- essarily those of SAE. The author is solely responsible for the content of the paper. A process is available by which discussions will be printed with the paper if it is published in SAE transactions. For permission to publish this paper in full or in part, contact the SAE Publications Division. Persons wishing to submit papers to be considered for a presentation or publication through SAE should send the manuscript or a 300 word abstract of a proposed manu- script to: Secretary, Engineering Activity Board, SAE. Printed in U.S.A. 90-1 203PG Downloaded from SAE International by North Carolina State Univ, Saturday, September 15, 2018ABSTRACT In September of 1991, Allison Transmission Division launched the World Transmission product line with the release of the MD transmission into production. Two years later, that product line is being enhanced with the introduction of the HD transmission. The HD transmission has undergone extensive development to ensure that the new features and options will meet the needs and expectations of the target marketplace. INTRODUCTION This paper focuses on the design and development of the HD transmission. The HD transmission is the largest model of the World Transmission product line being introduced by Allison Transmission Division. The first section of this paper will cover a description of the target marketplace for the HD transmission. This will include specific market requirements and a brief description of the HD features which are intended to fulfill those require- ments. The second section will go into a detailed description of the HD transmission's features and options. This will not only look at the mechanical gear box, but it will describe the electronic controls, and also available support equipment. The third and final section of this paper will discuss the develop- ment process that was conducted in order to provide a durable, reliable transmission for the target marketplace. TARGET MARKETPLACE MARKET REQUIREMENTS - Since the initial release of the first Allison commercial, on-highway transmission in 1972, market requirements have continued