Sonnax 4-5 Servo Piston Assembly - Ford 5R55S Transmission

Sonnax 4-5 Servo Piston Assembly for the Ford 5R55S transmission. Servo bore wear is the number one failure point on the 5R55S. Machined from high-strength materials with precision seal grooves to ensure proper hydraulic apply force and zero bypass leakage.

Worn pistons and servos are a primary cause of soft shifts, delayed engagement, and slipping in these transmissions. This replacement component restores factory apply pressure for firm, consistent shifts. Includes new seals where applicable.

Fitment: 2002-2010 Ford Explorer, 2002-2005 Mercury Mountaineer, 2002-2005 Lincoln LS

Brand: Sonnax