The AFL valve is a solenoid feed regulator valve that feeds the EPC solenoid and shift solenoids. The OE AFL valve design has a large reaction area and is highly affected by side loading, which wears the valve body bore. The EPC solenoid oscillates the torque signal and AFL oil, which increases valve action. As the bore wear increases, oil pressure is reduced to the shift solenoids, which causes solenoid and ratio codes. The same AFL oil loss results in lower line pressure. The improved Sonnax kit 77754-09K (4L60-E) eliminates these problems.
Due to the valve diameter and sleeve, this repair requires a reamer and reamer guide tool kit 77754-TL, which also services the 4L80-E.
March 02, 2016
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January 21, 2013
Topics: Vacuum Testing Vacuum Test Guides Transmission GM 4L60-E TransmissionRead Now
Contact a Sonnax Parts Distributor.