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  • Soft shifts & poor line rise
  • 3-4 Concerns


Wear at the 3-4 accumulator valve and/or bore, allowing loss of torque signal, 3-4 accumulator and/or line pressure.


Refurbish the worn bore and install the Sonnax oversized valve to restore correct hydraulic clearances and shift control.


Required tool kit F-84754-TL55 is no longer in production. Check with your distributor for availability.


Oversized 3-4 Accumulator Valve Kit
Part No. 84754-55K

GM units only

You need this if... View Instructions

To help control the 4th clutch apply pressure and shift feel, a 3-4 accumulator piston and an accumulator valve regulating fluid pressure are used. The 3-4 accumulator valve regulates line pressure using torque signal influence, and directs 3-4 accumulator pressure to the spring side of the piston, controlling the 4th clutch apply. Wear at the bore or valve can allow torque signal, 3-4 accumulator or line pressures to exhaust, resulting in various 3-4 shift complaints.

Reconditioning the bore and installing Sonnax oversized accumulator valve kit 84754-55K restores correct hydraulic clearance and shift control in GM units. For Volvo units, Sonnax offers 84754-58K.

  • Hardcoat anodized valve combats premature wear
  • Lengthened valve spool for better hydraulic sealing and stability
  • Annular grooves hydraulically center the valve to reduce wear
  • Valve
  • Spring

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 4T65-E Valve Body Layout

Gm 4t65 e thumb

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  • 84754 55k combo
  • 84754 55k

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.

  • 84754 55k test