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 (TH700-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 77701-076 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
Drop-in Zip Valve™ parts install quickly and easily

Learn More About Zip Valve™ Drop-In Repairs

More From This Category

Sonnax Shift Detent Spring Retainer, GM, Powerglide, Each

Sonnax Shift Detent Spring Retainer, GM, Powerglide, Each

$5.07

Sonnax Oversized Accumulator Pin, GM, 4T60, 4T60-E

Sonnax Oversized Accumulator Pin, GM, 4T60, 4T60-E

$18.26

RTS Transmission Flexplate, Converter, Dust Cover, Steel, Black Powdercoated, Chev GM Powerglide

RTS Transmission Flexplate, Converter, Dust Cover, Steel, Black Powdercoated, Chev GM Powerglide

$53.30

MANLEY Connecting Rod Pin Bushing, Bronze, 1.037 in. OD, .929 in. ID, .955 in. Length, Each

MANLEY Connecting Rod Pin Bushing, Bronze, 1.037 in. OD, .929 in. ID, .955 in. Length, Each

$22.80

TCI Clutch Hub, Steel, High Gear, GM, Powerglide, Each

TCI Clutch Hub, Steel, High Gear, GM, Powerglide, Each

$218.57

Motive Gear Differential Master Bearing Kit, Timken, For CADILLAC FLEETWOOD 1991–1996, Kit

Motive Gear Differential Master Bearing Kit, Timken, For CADILLAC FLEETWOOD 1991–1996, Kit

$323.30