Symptoms:

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

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:

The Sonnax drop-in TCC regulator valve kit has extended spool lands to operate in unworn areas of the bore and a lengthened shuttle valve to prevents the valve train from sticking.

6L45, 6L50, 6L80, 6L90

TCC Regulator Valve Kit
Part No. 104740-46K

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

Vehicles with GM 6L45, 6L50, 6L80 and 6L90 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.

For moderately worn bores, installing Sonnax TCC regulator valve kit 104740-46K will restore proper valve function resulting in proper TCC apply. The valve lands have been lengthened significantly, allowing the valves to operate in unworn portions of the casting bore to effectively seal against leakage.

  • Hardcoat anodized aluminum valves combat premature wear
  • Inboard and outboard spools on the TCC regulator valve have been made significantly longer to operate in unworn portions of the casting bore
  • Outboard shuttle valve has been made longer for better sealing and to prevent cocking in the bore
  • Restores proper valve function and TCC apply
  • Regulator Valve
  • Shuttle Valve
  • End Plug
  • Spring
  • 6L45, 6L50, 6L80, 6L90 TCC Regulator Valve Kit 104740-46K
  • 6L45, 6L50, 6L80, 6L90 TCC Regulator Valve Kit 104740-46K

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 TCC Regulator Valve Kit Vacuum Test Locations