• Erratic shift timing
  • Low line pressure
  • Low throttle pressure
  • Delayed Reverse
  • Oil leaks


Valves cycling in various bores strike the end plugs, creating excess clearance between plug and bore. Worn plugs can leak critical throttle and reverse pressure.


Sonnax drop-in O-ringed plug kit eliminates leakage at the bore plug.


O-Ringed End Plug Kit
Part No. 56947-LRG


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A4LD transmissions often have shift timing problems due to shift or accumulator oil circuit leakage caused by leaking end plugs in the valve body. A4LD valve assemblies incorporate end plugs to retain the valve train and seal the circuitry. As end plugs wear and circuit oil is lost, shift timing suffers. Installing Sonnax O-ring end plugs can eliminate this circuit leakage.

  • O-ring provides a positive seal
  • High-quality aluminum resists wear
  • Kit 56947-14K includes replacement O-ring plugs for the 1-2 shift valve, 2-3 shift valve, governor coast boost valve, 1-2 transition plug, throttle pressure boost valve and intermediate servo accumulator valve
  • Components are also available individually in Sonnax end plug kits 56947-SML, 56947-MED and 56947-LRG
  • Drop-in Zip Valve parts install quickly and easily

Additional O-rings have been added to kits.

  • End Plugs, Large (3)
  • O-Rings, Large (4)
  • A4LD O-Ringed End Plug Kit 56947-LRG