CarTech®, Inc.
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© 2015 by Jefferson Bryant
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Layout by Monica Seiberlich
ISBN 978-1-61325-268-0
Item No. SA369
Library of Congress Cataloging-in-Publication Data Available
Written, edited, and designed in the U.S.A.
Front Cover: General Motors equipped select muscle cars and certain trucks with the Chevy 12-bolt axle assembly. This proven limited-slip axle delivers exceptional durability and traction. It is also relatively easy and straightforward to rebuild. (Photo Courtesy Tony E. Huntimer)
Title Page: You can see the Chevy 10-bolt carrier inside the axle housing. When disassembling a limited-slip differential, you remove the C-Clip to remove the axle shafts.
Back Cover Photos
Top Left: The center pin is a potential failure point for the carrier. In this case, the pin broke around the locking bolt hole, allowing it to slide out. Luckily, the driver was just barely rolling and the differential was not under an enormous load, otherwise much more damage could have been done. When the pin came out, it locked up the differential. This could have split the case of the housing if it had happened at speed.
Top Right: Ring gears convert the engine’s rotation to forward motion, but there is more to selecting a gear set than just what size you think you need.
Bottom Left: The spring pack is used to keep the tension on the clutches. Most GM limited-slips use four springs and two plates, but some use an S-spring. You can tune the level of slippage with the springs. Stock Eaton GM limited-slip differentials use 400-pound springs.
Bottom Right: Here is a bad wear pattern, showing that the pinion is too close to the ring gear. Note the hard edge on the coast side; it looks like a shark fin. This would be very noisy and generate a lot of heat. The answer is a thinner pinion shim.
CONTENTS
Chapter 1: History and Identification
Chapter 2: Suspension Types and Differential Housings
Watt’s Linkage Rear Suspension
Triangulated Four-Link Rear Suspension
Project: Building a Universal Axle
Advanced Suspension Components
Project: Installing an A-Body Axle with Tubular Arms
Project: Updating Inside the Housing
Limited-Slip or Open Differential?
Axle Removal
Pinion Yoke Removal
Axle Shaft Removal
Carrier Removal
Pinion Removal
Cleaning the Housing
Project: 12-Bolt Brake Conversion for a 1967 Chevy Truck
Chapter 4: Assembly
Open Differentials
Limited-Slip Differentials