October 27, 2014
Listed GM 6-speed transmissions often set various trouble codes related to failures of fluid pressure switches that are internal to the transmission electro-hydraulic control module (TEHCM). These codes may be accompanied by TCC apply problems or shift irregularities such as slipping, flares, harsh application, and bind-ups. As time goes by, the laminated portions of the pressure switches can breach, preventing normal switch operation. If more than one switch breaks down, failsafe mode can be triggered. Since switches cannot be obtained through OE channels, replacement of the TEHCM was the only previous remedy available.
It is no longer necessary to replace the expensive TEHCM assembly to rectify this concern. Installing Sonnax pressure switch rebuild master pack 124740-28K restores normal switch operation, eliminating codes and providing renewed shift performance in all ranges.
Before installing kit, test switches to verify proper electrical operation. Kit repairs laminate disc and seal failures only; it will not rectify electrical breakdown. See instructions for details.
Sonnax valve body layouts provide a detailed overview of individual units making it quick and easy to determine what’s available for the specific valve body you’re working on. See all Sonnax valve body layouts.
October 27, 2014
February 19, 2015
October 28, 2014
September 30, 2005
All I need to say is WOW! Since getting the new tools and kit, I have done 4 transmissions and all went great. I want to say thank you to Sonnax for creating a kit that makes working on these transmissions a little easier.Rino