TM 9-2520-246-34-1 The information in the TB 43-0001-39 series is compiled from some of the Equipment Improvement Reports that you prepared on the equipment covered in this manual. Many of these articles result from comments, suggestions, and improvement recommen- dations that you submitted to the EIR program. The TB 43-0001-39 series contains information on equipment improvements, minor alterations, proposed Modification Work Orders (MWO’S) , warranties (if applicable), actions taken on some of your DA Form 2028’s (Recommended Changes to Publications), and advance information on proposed changes that may affect this manual. In addition, the more maintenance significant articles, including minor alterations, field–fixes, etc., that have a more permanent and continuing need in the field are republished in the Equipment Improvement Report and Maintenance Summary (EIR MS) for TARCOM Equipment (TM 43-0143). Refer to both of these publications (TB 43-0001-39 series and TM 43-0143) periodically, espe- cially the TB 43–0001– 39 series, for the most current and authoritative information on your equipment. The information will help you in doing your job better and will help in keeping you advised of the latest changes to this manual. Also refer to DA Pam 310-4, Index of Technical publications, and Appendix A, References, of this manual. 1-11. REPORTING IMPROVEMENT RECOMMENDATIONS . If your transmission, trans- fer or power takeoff needs improvement, let us know. Send us an EIR. you, the user, are the only one who can tell us what you don’t like about your equipment. Let us know why you don’t like the design. Tell us why a procedure is hard to perform. Put it on an SF 368 (Quality Deficiency Report). Mail it to us at: Commander, U.S. Army Automotive Material Readiness Command, ATTN: DRSTA-MT, Warren, Michigan 48090. We’ll send you a reply. 1-12. METRIC SYSTEM. The equipment/system described herein is nonmetric and does not require metric common or special tools. Therefore, metric units are not supplied. Tactical instructions, for sake of clarity, will also remain nonmetric. 1-13. QUALITY ASSURANCE/QUALITY CONTROL. Repair and replacement standards for transmissions, transmission transfers, and power takeoffs are given in chapter 2. By replacing the parts that do not meet the tolerances given in this manual for wear limits and adjustments, quality control of the equipment will be maintained. 1-14. DESCRIPTION. a. General. A short description covering each transmission, transmission trans- fer: and power takeoff is given in the following paragraphs. The descriptions are used to show direct support, general support, and depot maintenance personnel the different types and models of each unit. Differences between models are also given. b. Transmissions. (1) Transmission model 3053A (fig. 1-1) is a manual shift, synchromesh, selective gear type with five speeds forward and one reverse. The outer case is made of cast iron and gives support for the different bearing shafts and other parts of the transmission gear train. (2) Transmission model 3053A is a five-speed transmission with fourth speed being a direct drive and fifth speed an overdrive. The shift pattern for the trans- mission is shown in figure 1-2. c. Transmission Transfers. (1) Transmission transfer model T-136-21 and T-136-27 are two-speed syn- chromesh units driven from the transmission through a propeller shaft. The transfers send power to front and rear axles through propeller shafts. 1-4