Symptoms:

  • Code P0741, P0742
  • High TCC slip RPM
  • Overheated fluid
  • Failsafe mode
  • Harsh shifts
  • Harsh TCC apply
  • Loss of fuel economy

Cause:

Bore wear at the TCC regulator valve reduces TCC apply and converter charge pressure. A stuck TCC regulator valve causes either TCC slip or harsh apply.

Correction:

Ream to restore the bore and install Sonnax oversized TCC regulator valve kit to restore proper valve function.

6L45, 6L50, 6L80, 6L90

Oversized TCC Regulator Valve Kit
Part No. 104740-07K


You need this if... View Instructions Find a Distributor

Vehicles with listed GM transmissions may have a number of TCC apply problems. Bore wear at the TCC regulator valve can cause no TCC apply or slipping on engagement, harsh shifts, loss of performance and fuel economy, and fluid overheat. If the valve is stuck in the apply position, the result is harsh TCC apply. If the valve is stuck in the release position, no TCC apply or TCC slip will result. Reconditioning the bore and installing Sonnax oversized TCC regulator valve kit 104740-07K will restore proper valve function, resulting in proper TCC apply.

  • Hardcoat anodized aluminum valve combats premature wear
  • Restores proper valve function and TCC apply
  • TCC Regulator Valve
  • Shuttle Valve
  • End Plug
  • Spring

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
  • 6L45, 6L50, 6L80, 6L90 Oversized TCC Regulator Valve Kit 104740-07K
  • 6L45, 6L50, 6L80, 6L90 Oversized TCC Regulator Valve Kit 104740-07K

You need this if...

Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.

  • 6L45, 6L50, 6L80, 6L90 Oversized TCC Regulator Valve Kit Vacuum Test Locations