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Super Hold Servo Kit
Part No. 28821-09K

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Sonnax super hold servo kit 28821-09K dual piston design has 30% more apply area than the OE Powerglide servo. The patented design fits completely inside the case, and the external cover clearance is the same as original servos. The larger apply area will increase band apply force at your current line pressure or allows you to reduce line pressure by 20% to 30% while maintaining the same apply force. Improved sealing throughout reduces fluid loss and is optimized for low friction movement.

  • 30% More apply area
  • Allows line pressure to be reduced, freeing up horsepower
  • Dual seals for piston to case bore
  • Pin-to-case PTFE seal
  • Fits into the same space as a standard servo assembly
  • Servo Assembly
  • Cover Gasket
  • Case-to-Cover O-Ring
  • Return Spring
  • Servo Pin Seals (2) PTFE, 1 extra
  • Primary Piston Seals (2) PTFE

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  • 28821 09k