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125 / 125C Automatic Transmission Principles of Operation and Systematic Troubleshooting

gm 125 and 125C Automatic Transmission training bookgm 125 and 125C Automatic Transmission training book

Product ID 09-200-027

This Product Service Training 122 page book walks you through the principles of operation, from the mechanics to the hydraulic controls. The detailed text and color illustrations will instruct the reader in the mechanical power flow and hydraulic systems of this unit.
GM PST 17002.00-5

Manufacturer: GM
Coverage: THM 125 -C Automatic 3 Speed Transaxles
Pages: 122
Format: digital
Delivery: download

PRICE: $34.95
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dealer level specialty tools to properly repair without damaging components

This book can help anyone to understand the basic operation of a transmission and how to troubleshoot it properly. The only difference between the 125 and 125 c is the torque converter clutch hydraulic and electrical circuits. With this book you can understand what is failing with the transmission before tear down.

bulletSection 1 starts with a general description of the transmission and its components. It then progresses into an understanding of the torque converter, power flow, then summarizes the power flow.

Next is the hydraulic system and complete hydraulic circuits. Then finally into the torque converter clutch electrical controls for both applied and released states.

bulletSection 2 contains systematic troubleshooting flow charts for every possibility of malfunction. It includes the proper way to use a pressure gauge with expected readings, plus road test procedures.

It then progresses into explaining the causes of problems that resulted in a failure, with flow charts. Exploded views of the transmission and valve body are included.

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Product Service Training

These books are easy to understand, and applicable to a single subject. The book information is more in depth than even their own service manuals. The books include the original mechanic's notes and we strongly suggest that you read those notes with great care!

These books were never distributed outside of the manufacturers product service training channel.

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