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  • Engine chuggle
  • Early lockup
  • TCC shudder on coastdown


A weak converter clutch shift valve spring allows early TCC apply.


This spring is stiffer than the OE version and strong enough to stroke the converter clutch shift valve back and release the converter clutch.


Anti-Shudder Spring
Part No. 56995A

Package Quantity: 2

View Instructions

Converter clutch apply is controlled by two things: the converter clutch shift valve and converter clutch solenoid. The Sonnax spring 56995A will delay the converter clutch shift valve stroke by approximately 10 mph more than the factory spring, offering a later converter clutch apply. A secondary benefit is that if the converter clutch solenoid or solenoid electrical circuit fails in the enabled position, the Sonnax spring will ensure that the converter clutch releases before the vehicle comes to a stop, preventing engine chuggle.

  • Stronger spring delays lockup by approximately 10 mph.
  • Stronger spring will release the lockup if the TCC electrical circuit or solenoid fails.

This is a shudder related to the converter clutch shift valve, not the shuttle valve.

September 30, 2005

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