4L60E, 4L65E, 4L70E

2nd Gear Servo Release

Symptoms:

• Reduced 3-4 clutch life
• 2-3 Shift feel poor
• 3-2 Bind-up

Cause:
Inadequate metering of the 2nd band servo release oil.

Correction:
This part combines an orifice with a ball check valve to meter servo release oil.

Technicians would like to find a way to successfully extend the life of 3-4 clutches, and improve the 2-3 shift feel. They have been trying, with limited success, since the GM 4L60 (700-R4) and 4L60-E series transmissions were introduced. Inadequate metering of 2nd gear band servo release oil causes 3-4 clutch failure. The 3-4 clutch and 2nd gear band are not properly synchronized. Sonnax servo release check valve kit is a unique solution that combines an orifice with a ball check valve to resolve these problems.

• Improved design meters servo release oil, reducing 3-4 clutch failure
• Provides sufficient exhaust so that 3-2 downshifts are smooth
• Calibrates 3-4 clutch feed orifice without creating shift concerns

Kit Contains:

• O-Ring
• Valve

SONNAX Installation Instructions