Symptoms:

  • Code 39, 740, 1870
  • Falls out of lockup when hot
  • Overheated converter
  • Shudder
  • Low cooler flow

Cause:

Wear of the TCC apply valve bore allows leakage of TCC signal oil to exhaust and the apply valve to move into the TCC release position.

Correction:

Recondition the bore and install Sonnax oversized TCC apply valve kit to restore hydraulic integrity.

4T60, 4T60-E

Oversized TCC Apply Valve Kit
Part No. 84754-16K

'96-Earlier with steel valve


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

In GM 4T60 and 4T60-E units, the TCC apply valve acts as the switch valve for converter apply and release. The TCC regulator valve controls TCC apply pressure. Both the apply valve and the regulator valve can cause slip codes. When the apply valve is worn, it often returns to the un-apply position even though the TCC apply solenoid remains energized. Generally the apply valve causes larger changes in slip RPM as the converter cycles from apply to full release. The regulator valve causes a more gradual load and heat-sensitive slip. Check for changes in slip RPM with a scanner or changes in cooler flow with the Sonnaflow®. FM-01KA. Reconditioning the bore and installing Sonnax oversized TCC apply valve kit 84754-16K restores hydraulic integrity.

  • PTFE seal prevents loss of signal oil that strokes the valve
  • Oversized versions available to restore the valve body bore
  • Standard-size versions are drop-in replacements and do not require valve body removal
  • Tool kit services both early and late models
  • Valve
  • Seal PTFE
  • Spring
  • Material: Steel

  • 4T60, 4T60-E Oversized TCC Apply Valve Kit 84754-16K
  • 4T60, 4T60-E Oversized TCC Apply Valve Kit 84754-16K
  • 4T60, 4T60-E Oversized TCC Apply Valve Kit 84754-16K details

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.

4T60, 4T60-E Oversized TCC Apply Valve Kit Vacuum Test Locations