Description
Powerglide Super Hold Servo Kit, Sonnax 28821-09K.
Sonnax super hold servo kit 28821-09K is an all-in-one upgrade ideal for a competitive edge in GM Powerglide applications where racers are looking to reduce line pressure to free up horsepower. The kit’s dual piston design features 30% more apply area to increase band apply force at your current line pressure or allow you to reduce line pressure by 20% to 30% while maintaining the same apply force.
- Dual piston design for 30% more apply area
- Spring counteracts pin bias effect up to 275 psi
- Improved sealing throughout
- Low-profile design ensure adequate clearance
- 6061 Anodized billet aluminum cover
A common question is, “I have an extreme application, how do I choose between the Sonnax Smart-Tech® servo and the super hold servo?”
Both are track-proven in today’s high-power vehicles. With its ratio-style release and supported pin design, the Smart-Tech 28821-10K is the best all-around upgrade that eliminates EVERY problem associated with the OE servo. Racers looking to reduce line pressure for greater efficiency will most benefit from the super hold servo’s 30% more apply area.
- Servo Assembly
- Cover Gasket
- Case-to-Cover O-Ring
- Return Spring
- Servo Pin Seals (2) PTFE, 1 Extra
- Primary Piston Seals (2) PTFE
