Source: GM TechLink, July 2004:
This information applies to 2004 Light Duty Trucks, Corvette and GTO.
General Motors Powertrain has made a design change to oil pump to case oil seal on the 2004 4L60E (M30) and the 4L65E (M32). The new seal is a stamped molded seal and replaces the O-ring style seal previously used. The two seals are not interchangeable.
The new seal is being phased into production starting in March of 2004.
When servicing transmissions with the new design stamped molded seal, use following precautions:
- The outer diameter of the pump assembly and case bore must be clean and free of burrs or raised surfaces. Be aware of sharp edges that could damage the seal during installation.
- The seal should be clean and dry before installation. It does not require lubrication for installation.
- Before installation, inspect the seal for obvious damage.
- It is preferable to hand-start the seal, positioning the seal evenly around the case bore, before installing the torque converter housing.
- The seal can be easily removed by prying it out, typical of a pressed-on seal.
- The seal may be reused. However, throughly inspect the seal for:
-- Distortion of metal carrier or separation from the rubber seal
-- Cut, deformed, or damaged seal.
- The new stamped molded oil pump to case seal will not service transmissions produced before the design change, nor will the previous O-ring style seal work in place of the stamped molded seal.
- The new stamped molded seal requires that the oil pump be installed and torqued before installing the molded seal. The molded seal is seated into position by installing and torquing the torque converter housing.
An informational TSB is in process and SI is being updated to include the new service procedures for the new stamped molded oil pump to case seal.
- Thanks to Mark Gordon
Article ID: 431
Created: July 23, 2014
Last Updated: July 23, 2014
Author: Rob Loszewski
Online URL: https://www.corvetteactioncenter.com/tech/knowledgebase/article.php?id=431