• Various concerns depending on location of leaking end plug
  • Pressure loss


Worn, eroded end plugs allow loss of critical hydraulic pressure.


Sonnax O-ringed end plugs restore correct circuit pressures. The O-ring provides additional sealing to reduce hydraulic losses at critical circuits.

A750E, A750F

O-Ringed End Plug Kit
Part No. 147741-31K

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

The primary design function of the OE end plug is to prevent critical pressure loss by capping the bore. OE end plugs rely entirely on small clearances between the end plug and bore to confine hydraulic fluid under fluctuating pressure. End plugs are often tasked with a secondary role functioning as a spring stop or valve stop. The repetitious and varying actions of fluid pressure, spring motion and valve impact cause wear at the end plug and bore mating surface, and can distort the shape of the end plug. High pressure fluid that leaks through the clearance gap can, with time, erode the surface material of both end plug and bore. Eventually, the cumulative loss of hydraulic integrity leads to low pressure in critical circuits. Complaints vary depending on the location of the worn end plug, but are always related to pressure losses. Sonnax O-ringed end plug kit 147741-31K replaces worn, distorted or eroded end plugs in Toyota A750E and A750F transmissions. Sonnax end plugs have an O-ring seal that reduces leakage further by blocking off worn areas of the bore which the new end pllug alone could not seal.

  • No special tools required
  • Minimal end plug-to-bore clearance with added O-ring for positive seal
  • Drop-in Zip Valve™ parts install quickly and easily
I.D. Valve Name End Plug Dia. Installed Seal Position O-Ring Size
Lower Valve Body
A Clutch Control 11mm Outboard Medium
B Clutch Apply Control 11mm Outboard Medium
Upper Valve Body No. 1
C Clutch Lock 11mm Outboard Medium
D Lockup Relay 11mm Outboard Medium
E 1-2 Shift 11mm Outboard Medium
F 2-3 Shift 11mm Outboard Medium
G 3-4 Shift 11mm Inboard Medium
H Brake Control 12mm Outboard Medium
I Secondary Regulator 14mm Outboard Large
Learn More About Zip Valve™ Drop-In Repairs
  • End Plugs, 11mm (7)
  • End Plug, 12mm
  • O-Rings, Medium (14) 6 Extra
  • End Plug, 14mm
  • O-Rings, Large (2) 1 Extra
  • Installation Screw Not Shown

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.

Toyota/Lexus A750E/F Valve Body Layout

Toyota/Lexus A750E/F Valve Body Layout
  • A750E, A750F O-Ringed End Plug Kit 147741-31K
  • A750E, A750F O-Ringed End Plug Kit 147741-31K

You need this if...

Vacuum test fails to yield 18 in-Hg or higher in the locations shown.