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Fitment Type: Direct Replacement

Items Included: Servo Piston, Cover, Gasket and Seals, bolts

Manufacturer Part Number: 28821-08K

Mounting Hardware Included: No

Drive Type: 2WD

Material: Aluminum

Bundle Listing: No

Brand: Sonnax

Type: Servo

Interchange Part Number: 103907CHPK

Manufacturer Warranty: Unspecified Length

Surface Finish: New

Vintage Part: Yes

Country/Region of Manufacture: United States

Performance Part: Yes

Aluminum Powerglide Low Band Servo Kit
Fits 1962-73

Sonnax Part No. 28821-08K

Dual-seal design, PTFE sealing ring style, Non-anodized

 GM Powerglides used for drag racing generate higher line pressure than the OE servo piston can withstand. At pressures over 200 psi, the OE piston can crack, resulting in transmission failure. Sonnax servo piston and cover kit 28821-08K improves transmission performance and durability under high-pressure conditions.
  • High-strength billet aluminum piston also features a rounded profile for better stress distribution
  • Dual PTFE seals improve sealing, are low-friction and interchangeable with the OE cast aluminum seal ring
  • Lightweight, billet aluminum cover replaces heavy, cast-iron OE cover
  • Easy to install, no case modifications required
Contents
  • Cover Non-Anodized
  • Pipe Plug
  • Hex Head Bolts (3)
  • Cover O-Ring
  • Cover Gasket
  • Piston
  • Piston Seals (2) PTFE
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