Muncie 4-Speed Transmissions. Paul Cangialosi

      

      

      CarTech®, Inc.

      39966 Grand Avenue

      North Branch, MN 55056

      Phone: [phone] or 800-551-4754

      Fax: [phone]

       www.cartechbooks.com

      © 2014 by Paul Cangialosi

      All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage and retrieval system, without prior permission from the Publisher. All text, photographs, and artwork are the property of the Author unless otherwise noted or credited.

      The information in this work is true and complete to the best of our knowledge. However, all information is presented without any guarantee on the part of the Author or Publisher, who also disclaim any liability incurred in connection with the use of the information and any implied warranties of merchantability or fitness for a particular purpose. Readers are responsible for taking suitable and appropriate safety measures when performing any of the operations or activities described in this work.

      All trademarks, trade names, model names and numbers, and other product designations referred to herein are the property of their respective owners and are used solely for identification purposes. This work is a publication of CarTech, Inc., and has not been licensed, approved, sponsored, or endorsed by any other person or entity. The Publisher is not associated with any product, service, or vendor mentioned in this book, and does not endorse the products or services of any vendor mentioned in this book.

      Edit by Paul Johnson

      Layout by Chris Fayers

      ISBN 978-1-61325-211-6

      Item No. SA338

       Front Cover:

       State-of-the-art replacement Muncie case components and gears set a new standard for rebuilding an old, worn-out Muncie 4-speed.

       Title Page:

       This is a completed SPEC-25. The special Teflon coating reduces internal friction and heat: The exterior becomes a non-stick surface and gasket surfaces clean up very quickly. Plans are in the works for new-style NASCAR synchro assemblies and more ratios, so a SPEC-35 will most definitely be in the future!

       Back Cover Photos:

       Top

       Usually the gear and 3-4 synchro hub dislodge if you hold third gear and gently tap on the front of the mainshaft. Later units have hardened hubs with extremely tight press fits, and you must use a press to remove them. If the gear and hub do not come off, do not use a hammer to try to remove them. The tip of the mainshaft is easily damaged. Use a press and bearing clamp on third gear for removal.

       Middle:

       Lift the countergear out of the case. If the case was damaged from a gear explosion, the thrust washers are often jammed from debris. If that has happened, stand the case on its front face, so that the loose gear doesn’t cock or move off center, and rotate it as you remove it.

       Bottom Left:

       The bronze synchro ring has a 6-degree internal taper that matches the taper on the gear’s synchro cone. As it is forced up against the cone, it eventually causes the output shaft to run at the same speed as the gear. It’s essentially a cone clutch.

       Bottom Right:

       I never press directly on gear surfaces. The lower gear has an old bearing race against it. This grabs closer to the inside diameter of the gear to prevent press-surface contact with the gear teeth.

      CONTENTS

Acknowledgments

Introduction

What is a Workbench® Book?

Chapter 1: History and Evolution

Happy Accidents Create the Muncie

Muncie Design Changes

Available Gear Ratios

Chapter 2: Muncie 4-Speed Identification

Muncie RPO Codes

Main Case Casting Numbers

Serial Numbers

       Main Cases

       Service Cases and Transmissions

       Extension Housings and Sidecovers

       Midplate Castings

       Ratio Identification

       Hardware and Tags

       Chapter 3: How Muncie 4-Speeds Work

       Forward Gears

       Reverse Gears

       Lack of Front Seal

       Design Features

       Diagnosing Common Problems

       Shifter Considerations

       Chapter 4: Inspection and Repair

       Cleaning

       External Case Components

       Gears, Synchros and Shafts

       Bearings and Bearing Surfaces

       Chapter 5: Rebuilding Your Muncie

       Muncie Rebuild Kit

       Workflow Process

       Chapter 6: High-Performance Muncies

       Auto Gear Equipment

       High-Performance Gearsets

       Muncie Design Features