A/T - New Band Assemblies

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Bulletin: 91-74T60-12

Date: May '91

Ref. No.: 91-180-74T60

Corp. Ref. No.: 077125R


SUBJECT: NEW 1-2 AND REVERSE BANDS - NO SELECTIVE BAND APPLY PINS REQUIRED (4T60)

MODELS AFFECTED: 1984-1991 CENTURY
1985-1990 ELECTRA/PARK AVENUE
1986-1991 LESABRE
1986-1990 RIVIERA
1988-1990 REATTA
1988-1991 REGAL





BULLETIN COVERS: (Figures 1 and 2)

The new 1-2 and reverse band assemblies do not require selective band apply pins. A new manufacturing process machines the area where the case anchor pins contact the band. With this new process, all the 1-2 bands are the same size and all the reverse bands are the same size. With the bands all the same size, selective band apply pins are not required.

SERVICE PROCEDURE:

When replacing a 1984 through 1991 model year transaxle 1-2 or reverse band, it is not necessary to measure the selective band apply pin(s), provided the band service package contains an instruction sheet about the non-selective band apply pin.

IMPORTANT: If ordering a new 1-2 or reverse band, the correct band apply pin must be used with the band. The correct band apply pin is not included with the new band service package(s) (that includes an instruction sheet about the non-selective band apply pin). The proper band apply pin must be ordered separately.

NOTICE: If replacing a 1-2 band with the new 1-2 band listed in this bulletin, the 1-2 band stop (on models so equipped) must be removed prior to installing the band. The 1-2 band stop, if not removed, would cause the new 1-2 band to remain partly applied, distressing the 1-2 band. Reference Service Bulletin, 90-7440-8.


IMPORTANT: The new reverse band also has the new friction material that will help decrease reverse engagement concerns. Reference Service Bulletin 90-7440-12.

DATE OF PRODUCTION CHANGE:

Beginning July 2, 1990 (Julian Date 183), all 1991 Hydra-Matic 4T60 transaxles were built with the new 1-2 and reverse band assemblies.

SERVICE PARTS INFORMATION:

The new bands will replace the previous bands.

Part Model
Number Description Year Model Usage

8675986 Package - Reverse Band Asm. 1984-91 All
- Reverse Band Assembly
- Instruction Sheet

8656543 Pin - Reverse Band Apply 1984-91 All

8675987 Package - 1-2 Band Asm. 1984-91 All
- 1-2 Band Assembly
- Instruction Sheet

8656540 Pin - 1-2 Band Apply 1984-91

Parts are currently available from GMSPO.

SERVICE MANUAL REFERENCE:

Refer to the appropriate Service Manual for proper disassembly and assembly procedures. The 1991 Service Manual shows the procedure to measure the 1-2 and reverse band apply pins and should be disregarded (except for early introduction 1991 Regal models built before the production change date).