Seville V8-273 4.5L (1989)
Band: All Technical Service Bulletins
A/T - 4T60 New 1-2 and Reverse Bands
NO.: 91-I-49
DATE: April, 1991
GROUP: 7
CORP. NO.: 077125R
SUBJECT: NEW 1-2 AND REVERSE BANDS - NO SELECTIVE BAND APPLY PINS REQUIRED ON 1985-1990 HYDRA-MATIC 4T60
TRANSAXLES
New 1-2 and reverse band assemblies went into production on July 2, 1990 (Julian Date 183) and have superseded previously available service parts.
Because of a new manufacturing process, all the 1-2 bands are the same size and all the reverse bands are the same size, eliminating the need for
selective band apply pins. There is no longer a need to measure for selective band apply pins for the entire normal service life of the band.
When installing these new bands in 1985-1990 Hydra-Matic 4T60 transaxles, it will be necessary to replace the original selective band apply pin with a
new nonselective band apply pin which must be ordered separately. An instruction sheet will be included with the new reverse and 1-2 band packages
that has information on the apply pins.
The following service parts are currently available from GMSPO:
P/N
Description
Usage
Supersedes
8675986
Package - Reverse Band Assembly
1985-1990 4T60
8668012
^ Reverse Band Assembly
8675152
^ Instruction Sheet
8656543
Pin - Reverse Band Apply
1985-1990 4T60
^ Nonselective
8675987
Package - 1-2 Band Assembly
1985-1990 4T60
8658478
^ 1-2 Band Assembly
8668984
^ Instruction Sheet
8656540
Pin - 1-2 Band Apply
1985-1990 4T60
^ Nonselective
If replacing a 1-2 band assembly with the new 1-2 band listed in this bulletin, it will be necessary to remove the 1-2 band stop (on models so equipped).
Refer to Service Bulletin T-89-135, Group 7, for 1-2 band stop removal procedure. The apply pin engagement area on the new 1-2 band is almost twice
as wide as the previous style. This increased area makes for a larger "target" for the 1-2 band apply pin and eliminates the need for the 1-2 band stop.
Transaxles built before January 16, 1990 (Julian Date 016) were built with a band stop and with a selective 1-2 band and apply pin. Transaxles built
between January 16, 1990 (Julian Date 016) and July 2, 1990 (Julian Date 183) were built without a band stop but still with a selective 1-2 band and
apply pin.
IMPORTANT: Using the new 1-2 band assembly with a 1-2 band stop may result in a durability concern.
If replacing a reverse band assembly, the new reverse band also has the new friction material that will help decrease reverse engagement concerns. Refer
to Cadillac Service Bulletin T-90-89, Group 7.
Refer to the appropriate Cadiiiac Service Information Manual for the required service procedures.
