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For 1990-2009 cars only

Info - Automatic Transmission Serial Number and Site Code Locations

Subject:Automatic Transmission Serial Number and Site Code Locations

Models:2003 and Prior Passenger Cars and Trucks
with North American Automatic Transmissions



General Motors automatic transmissions fall into two categories: those manufactured "by GM" (OEM) and those manufactured "for GM" (REMAN). Only OEM transmissions are used in the production of new GM vehicles. Goodwrench® service transmissions can be either OEM or REMAN. All Goodwrench® REMAN transmissions are identified by a green metal tag with the words "Manufactured for GM" except for Allison®, 4L30E (Catera) and 5L40E (CTS).

    • OEM = blue or black tag = "by GM"
    • REMAN = green tag = "for GM" (except for Allison®, Catera and CTS)

Remanufactured Transmission Serial and Site Code Number Locations

Other than the exceptions shown above, all North American Remanufactured transmissions use the same green tag shown below.

Important: When reporting serial and site code numbers, use the top row of characters followed by the bottom row with no spaces between any of these characters. Refer to the example below.

The Allison®-built transmissions, as well as the 4L30E (Catera) and 5L40 (CTS) do not have green REMAN tags. Refer to the appropriate section in this bulletin for each of these transmissions' correct OEM and REMAN serial numbers.

Goodwrench® Transmission Label (green background)


Object Number: 891999  Size: SH

Serial number: 17DPH600103298206

Require all numbers without spaces

OEM Transmission Serial and Site Code Number Locations

Front Wheel Drive Transmissions

The transmission ID tag is usually located on the side of the case facing the rear of the vehicle.

3T40 (OEM) MD9


Object Number: 892003  Size: SF
(1)Tag Location
(2)Serial Number

4T40E/4T45E (OEM) MN4/MN5


Object Number: 892005  Size: SF
(1)Tag Location
(2)Site Plant
(3)Serial Number

4T60E (OEM) M13


Object Number: 892006  Size: SF
(1)Tag Location
(2)Site Plant
(3)Serial Number

4T65E (OEM) M15/MN3/MN7


Object Number: 892007  Size: SF
(1)Tag Location
(2)Site Plant
(3)Serial Number

4T80E (OEM) MH1


Object Number: 892008  Size: SF
(1)Tag Location
(2)Site Plant
(3)Serial Number

Rear Wheel Drive Transmissions

 

4L30E (OEM) ML4 (Cadillac Catera 97-01)


Object Number: 893148  Size: SF
(1)Serial Number
(2)Tag Location

5L40E (OEM) M82 (Cadillac CTS)


Object Number: 893150  Size: MF
(1)OEM
(2)Remanufactured
(3)Part Number
(4)Serial Number
(5)Tag Location

4L60E (OEM) M30


Object Number: 892014  Size: MF
(1)Location
(2)Serial Number
(3)Optional Transmission Identification Location
(4)Transmission Identification Location

(No ID tag on transmission; serial number is stamped on case)

4L80E/4L85E (OEM) MT1/MN8


Object Number: 892018  Size: SF
(1)Tag Location

Allison® 1000 Series (OEM) M74

The Allison® LCT 1000 automatic transmission ID tag (1) is located on the right (passenger side), just rear of the PTO (power take off) cover.


Object Number: 892019  Size: MH

Use the model number (1), the date of manufacture number (2) and the serial number (3) for reporting purposes.

For example: 1000XXXXXYYYYYYYYYY (1000 + 5 characters + 10 characters).


Object Number: 893146  Size: SH
(1)Model (Series)
(2)Date of Manufacture
(3)Serial Number