SonnaxServo Piston Kit

The overdrive servo piston in Jatco/Nissan JR403E units is prone to cracking, allowing apply oil leakage that causes poor 3-4 shift quality and burned bands. The OE servo cover bolts stretch and break under normal use. As the cover becomes loose, it allows the piston to cock and break. Sonnax overdrive servo piston pit 62170-01K is thicker and stronger and will not break like the OE pistons do. Piston is made from billet aluminum for greater strength and wear resistance The 88mm (3.46") 4th piston can be used to upgrade from the smaller 75mm (2.953") 4th piston when used with a larger piston housing High-strength bolts will not stretch, and keep cover firmly secured

Servo Piston Kit; Overdrive, Includes D-Ring and Bolts