Symptoms:

  • Pressure switch codes
  • Switch codes
  • Pressure control out-of-range codes
  • Slips, flares & bind-ups
  • Failsafe mode
  • Erratic TCC apply
  • Harsh shifts
  • Shift codes

Cause:

OE pressure switch laminate disc breached, preventing proper switch operation.

Correction:

Salvage the transmission control unit and restore normal shift operation by installing Sonnax pressure switch rebuild kit.

Warning:

Sonnax pressure switch rebuild kit 124740-70K replaces 124740-30K which is no longer in production.

Required tool kit 124740-TL70 replaces 124740-TL30 which is no longer in production.

6L45, 6L50, 6L80, 6L90, 6T70 (Gen. 1), 6T75 (Gen. 1)

Pressure Switch Rebuild Kit
Part No. 124740-70K


View Instructions Find a Distributor

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 kit 124740-70K restores normal switch operation, eliminating codes and providing renewed shift performance in all ranges.

  • Allows salvage of expensive TEHCM
  • Kit includes enough discs and seals to rebuild 10 TEHCM units

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.

  • Laminate Discs (40)
  • Seals (40)

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.

GM 6L45, 6L50, 6L80, 6L90 Valve Body Layout

GM 6L45, 6L50, 6L80, 6L90 Valve Body Layout

GM 6T70/75 (Gen. 1) Valve Body Layout

GM 6T70/75 (Gen. 1) Valve Body Layout
  • 6L45, 6L50, 6L80, 6L90, 6T70 (Gen. 1), 6T75 (Gen. 1) Pressure Switch Rebuild Kit 124740-70K

Videos

How Rebuild TEHCM Pressure Switches in GM 6L45/50/80/90 & Gen. 1 6T70/75 Transmissions
 

The 6T70 Pressure Switch Rebuild Kit has saved me a TON of money!

J. Yarbrough
Certified Transmissions