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  • Clutch failure
  • Band failure
  • Solenoid performance codes
  • Low solenoid feed pressure
  • 2-3 Neutral
  • No 4th
  • 2nd Gear starts
  • Code 68, 85, 86, 87
  • Wrong gear starts


Actuator feed limit bore wear results in low pressure at shift and EPC solenoids.


Redesigned anodized AFL valve regulates pressure while the wear-resistant sleeve re-establishes hydraulic integrity.

4L80-E, 4L85-E

Actuator Feed Limit Valve Kit
Part No. 34200-16K

View Instructions

The actuator feed limit (AFL) valve in GM 4L80-E units has a large reaction area and is greatly affected by side loading, which wears the valve body bore. The EPC solenoid oscillates the torque signal and AFL oil, which increases valve action and accelerates wear. As 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.

Installing the Sonnax AFL valve kit 34200-16K corrects AFL oil pressure loss, restoring shift solenoid pressure to prevent wrong gear starts and other shift concerns. The hard-coat anodized valve is extremely wear resistant, and annular grooves have been added to minimize the effect of side loading. The Sonnax wear-resistant sleeve provides more valve contact area, providing additional support and further reducing valve and bore wear.

  • Kit includes wear-resistant sleeve and anodized valve with annular grooves to prevent side loading
  • Valve operates in full-contact sleeve, providing 54% more support
  • Boosts oil pressure to the shift solenoids
  • Eliminates AFL oil loss, corrects low line pressure
  • Valve
  • Sleeve
  • Long Spring
  • Short Spring
  • Retaining Clip

February 21, 2013

GM 4L80-E Vacuum Test Guide

Topics: Vacuum Testing Vacuum Test Guides Transmission GM 4L80-E Transmission

Read Now

  • 34200 16k combo
  • 34200 16k