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 28821-05K improves transmission performance and durability under high-pressure conditions.

• High-strength billet aluminum piston also features a rounded profile for better stress distribution
• 双重聚四氟乙烯密封小鬼rove 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