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A/T - New 2-4 Band, Apply/Anchor Brackets, Lube Window

89pontiac26

Bulletin Number: 90-7-20
Reference Number: 977161
Publish Date: 12/89
Subject: 2-4 BAND,CHANGES - APPLY/ANCHOR BRACKETS AND NEW LUBE WINDOW

Models
Affected: 1982-90 FIREBIRD MODELS

Figure 1 - 2-4 Band Assembly:




Figure 2 - THM 700-R4/HYDRA-MATIC 4L60 Transmission Identification Information:




BULLETIN COVERS: (Figure 1)

A new HYDRA-MATIC 4L60 transmission 2-4 band with changes to the apply and anchor brackets, locating tabs, and the addition of a "lube window". The lube window was added to direct lubricating transmission fluid to the band friction material while the band is not applied. Structural changes to the apply and anchor brackets increase their durability and the locating tabs were added to aid in assembly.

DATE OF PRODUCTION CHANGE: (Figure 2)

Starting September 8, 1989 (Julian Date 251), all HYDRA-MATIC 4L60 transmissions were built using the new 2-4 band assembly.

SERVICE PARTS INFORMATION:

The new band is interchangeable with the previous band and should be used for service whenever possible.

Part Name Previous Part Number New Part Number

Band Assembly - 2/4 8654144 8673175

Parts are currently available from GMSPO.

SERVICE MANUAL REFERENCE:

Refer to the HYDRA-MATIC 4L60 Unit Repair section of the appropriate Service Manual for removal and installation of the 2-4 band.