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  • Code P0741
  • Converter shudder
  • Falls out of lockup when hot
  • High TCC slip RPM
  • No lockup


Continuous oscillation of the converter apply valve in the cast-aluminum bore causes bore wear that prevents the valve from stroking to the lock-up position.


The Sonnax kit provides a positive seal to ensure proper valve stroke, and more valve support to prevent side loading that leads to wear.


TCC Apply Valve Kit
Part No. 84754-43K

You need this if... View Instructions

Continuous oscillation of the converter apply valve in the cast-aluminum bore causes bore wear, particularly at the TCC signal valve spool closest to the solenoid. Wear in this area allows TCC signal oil to leak, which inhibits the valve from stroking to the lockup position. Due to the valve body casting design and oil flow, this valve is also subject to extreme side loading, which increases the wear rate. Early OE versions of this valve were made from non-anodized aluminum, and show significant wear marks.

  • Hardcoat anodized aluminum valve with an expandable PTFE seal on the TCC signal valve spool provides a positive seal to ensure proper stroking of the valve.
  • The most inward Sonnax valve spool is almost 2.5 times longer then the OE spool, creating more valve-to-bore sealing area.
  • Greater sealing area combined with annular grooves allows the valve to stay centered in the bore and prevents side loading.
  • An extra PTFE seal and a new spring to fit within the valve spring pocket are included in the kit.
  • A replacement O-ring has been included for the OE end plug, to be used after inspecting the TCC regulated apply valve.

Always inspect the TCC regulated apply valve for wear. The O-ring in this kit should be used to replace the original end plug O-ring after inspection. Worn valves or bores can be repaired using the Sonnax TCC regulated apply valve and sleeve kit 84754-34K.

  • Valve
  • PTFE Seals (2) 1 extra
  • Spring
  • O-Ring

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 4T65-E Valve Body Layout

Gm 4t65 e thumb

March 21, 2013

GM 4T65-E Vacuum Test Guide

Topics: Vacuum Test Guides Vacuum Testing Transmission GM 4T65-E Transmission

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  • 84754 43k combo
  • 84754 43k

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.

  • 84754 43k in test