Vehicles with listed Ford and GM transmissions may exhibit no line rise or low line pressure due to excess wear in the isolator valve bore. The isolator valve is in the main line pressure circuit and acts as a damper to smooth pulses from the pressure control solenoid. In addition to this wear, the OE isolator spring is under high stress and commonly breaks. Spring failure allows the end plug to shift toward the middle of valve body, allowing unrestricted exhaust for main line pressure. Spring breakage can also cause isolator valve to jam in the bore, preventing the dampening effect that protects against line pressure instability. Either of these concerns can lead to undesirable shift operation and burned clutches. Installing Sonnax isolator valve kit 124740-03K restores proper line pressure control for renewed shift feel and performance.

O-Rings added to valve and end plug to ensure positive seal
Annular grooves help center valve in bore to reduce future side-load wear
Spring shot-peened to reduce fatigue and eliminate premature failure
Drop-in Zip Valve™ parts install quickly and easily

Learn More About Zip Valve™ Drop-In Repairs

More From This Category

MANLEY Valve, Severe Duty, Intake, 2.325 in. Head Dia, 0.3415 in. Stem Dia, 6.59 in. Length, BBC, Set of 8

MANLEY Valve, Severe Duty, Intake, 2.325 in. Head Dia, 0.3415 in. Stem Dia, 6.59 in. Length, BBC, Set of 8

$628.35

MANLEY Valve, Street Flo, Exhaust, 1.55 in. Head Dia, 0.3415 in. Stem Dia, 5.08 in. Length, For Ford SB, Set of 8

MANLEY Valve, Street Flo, Exhaust, 1.55 in. Head Dia, 0.3415 in. Stem Dia, 5.08 in. Length, For Ford SB, Set of 8

$280.36

Sonnax Afl/Solenoid Pressure Regulator Valve Kit, Ford, 6F50/55, 6T70/75 Gen I, Each

Sonnax Afl/Solenoid Pressure Regulator Valve Kit, Ford, 6F50/55, 6T70/75 Gen I, Each

$121.22

MANLEY Valve, Severe Duty, Exhaust, 1.9 in. Head Dia, 0.3415 in. Stem Dia, 5.522 in. Length, Set of 8

MANLEY Valve, Severe Duty, Exhaust, 1.9 in. Head Dia, 0.3415 in. Stem Dia, 5.522 in. Length, Set of 8

$607.34

MANLEY Valve, Custom, Titanium, .3415 in. Stem Dia, Each

MANLEY Valve, Custom, Titanium, .3415 in. Stem Dia, Each

$326.62

MANLEY Valve, Race Flo, Intake, 35.5 mm Head Dia, 5.5 mm Stem Dia, 109.22 mm Length, For Honda, Set of 8

MANLEY Valve, Race Flo, Intake, 35.5 mm Head Dia, 5.5 mm Stem Dia, 109.22 mm Length, For Honda, Set of 8

$399.33