Symptoms:

  • Solenoid performance codes
  • Wrong gear starts
  • Clutch failure

Cause:

Excess bore wear at AFL (actuator feed limit—GM) or solenoid pressure regulator (Ford) bore allows pressure loss that causes driveability concerns.

Correction:

Recover hydraulic control and renew shift operation by reconditioning the bore and installing Sonnax oversized AFL/solenoid pressure regulator valve.

6F50, 6F55, 6T70 (Gen. 1), 6T75 (Gen. 1)

Oversized AFL/Solenoid Pressure Regulator Valve
Part No. 124740-01


You need this if... View Instructions Find a Distributor

In Ford 6F50/55 and first generation GM 6T70/75 units, AFL/solenoid pressure regulator bore wear results in low pressure at the shift and control solenoid valve assembly. The OE valve has a large reaction area and is highly affected by side-loading, which wears the valve body bore. As the bore wear increases, oil pressure is reduced to the shift solenoids, which causes solenoid and ratio codes. This also results in lower line pressure.

Sonnax oversized AFL/solenoid pressure regulator valve 124740-01 is a solenoid feed regulator valve that feeds the control solenoid valve assembly. The valve, which is hardcoat anodized to reduce wear, will restore hydraulic control to the shift solenoids.

Sonnax valve body layouts provide a detailed overview of individual units making it quick and easy to determine what’s available for the specific valve body you’re working on. See all Sonnax valve body layouts.

GM Gen. 1 6T70, 6T75 Valve Body Layout

GM Gen. 1 6T70, 6T75 Valve Body Layout

Ford 6F50, 6F55 Valve Body Layout

Ford 6F50, 6F55 Valve Body Layout
  • 6F50, 6F55, 6T70 (Gen. 1), 6T75 (Gen. 1) Oversized AFL/Solenoid Pressure Regulator Valve 124740-01
  • 6F50, 6F55, 6T70 (Gen. 1), 6T75 (Gen. 1) Oversized AFL/Solenoid Pressure Regulator Valve 124740-01

You need this if...

Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.

6F50, 6F55, 6T70 (Gen. 1), 6T75 (Gen. 1) Oversized AFL/Solenoid Pressure Regulator Valve Vacuum Test Locations