HYDRA-MATIC 4780E Transmission - Improvements for 1998
| Subject: | NPR EFI Hydra-Matic 4L80-E Transmission Improvements for 1998 |
| Models: | 1999 NPR EFI Models |
| Attention: | This Service Bulletin is intended for use by professional, qualified technicians. Attempting repairs or service without the appropriate training, tools, and equipment could cause injury to you or others and damage to your vehicle that may cause it not to operate properly. |
Service Information
The following product updates have been implemented on the Hydra-Matic 4L80-E transmission during the 1998 model year.
Updated Seal Material Improvements Description
Legend:
219 - Overrun Clutch Housing Oil Seal Ring
639 - Direct Clutch Housing Oil Seal Ring
640 - Center Support Assembly
The direct clutch housing oil seal ring (639) and the overrun clutch housing oil seal ring (218) material is now a "PEEK" seal ring material with a double step joint design.
Updated Torque Converter Bushing Improvement Description
Legend:
202 - Torque Converter Bushing
203 - Oil Pump Body Assembly
The torque converter busing (202) is 0.140 inch longer and the oil pump body casting (203) was modified to accommodate the new bushing.
Update Identification
This product update was implemented in production on all 1998 4L80-E models S.O.P. (Start of Production)
Effect on Service Description
The direct clutch housing oil seal ring and the overrun clutch housing oil seal ring will not service past model year 4L80-E transmissions.
The installation and sizing tools are no longer required to install these oil seal rings.
The oil pump body assembly will service all model year oil pump covers.
Parts Information
These service parts a not available from AIPDN at this time.
