Unexplained band failure in Powerglides is a common problem that can be overcome by understanding the servo pin bias effect. This video demonstrates how the servo performs at high pressures when fitted with an OE, light aftermarket or Sonnax race-calibrated spring, available as a standalone component or in Sonnax 28821-20K. The video dramatically shows the pin bias effect in action, and why overcoming this built-in design flaw of the Powerglide servo is the only way to prevent “mystery” band failures.
Learn more about the servo pin bias effect.
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August 23, 2017
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