Symptoms:

  • Clutch failure
  • Soft shifts
  • Harsh shifts
  • Low line pressure
  • High line pressure
  • High line pressure in Reverse
  • Low line rise
  • Low converter pressure
  • Overheating

Cause:

Continuous oscillation of the pressure regulator valve causes valve body wear, resulting in line pressure irregularities and valve instability.

Correction:

Sonnax oversized main pressure regulator and boost valve kit allows line pressure function and control to be restored.

A750E, A750F, A760E, A760F, A760H, A761E, A960E, A960F, AB60E, AB60F

Oversized Main Pressure Regulator & Boost Valve Kit
Part No. 147741-04K


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

Toyota/Lexus A750, A760, A960 and AB60 series transmissions may exhibit multiple line pressure-related problems due to excessive wear in the main pressure regulator bore. Wear at the inboard regulating spool allows critical line pressure fluid to cross leak into the sump circuit, resulting in excess pressure and reduced cooler/converter flow. Sleeve wear at the reverse boost valve creates excessively high line pressure. Sleeve wear at the cutback valve allows oil loss resulting in poor line rise and burnt clutches. Sonnax oversized main pressure regulator and boost valve kit 147741-04K allows the bore to be refurbished, and the hydraulic integrity restored for proper line pressure in all ranges.

  • Pressure regulator valve is made from high-quality, hardened steel to resist wear
  • Inner spool has annular groove to reduce side loading that causes wear
  • Kit includes an increased ratio boost valve assembly specially designed to work with the oversized regulator valve
  • Pressure Regulator Valve
  • Outer Boost Valve
  • Inner Boost Valve
  • Boost Sleeve

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 A760E/F/H Series Valve Body Layout

Toyota A760E/F/H Series Valve Body Layout

Toyota/Lexus A750E/F Valve Body Layout

Toyota/Lexus A750E/F Valve Body Layout
  • A750E, A750F, A760E, A760F, A760H, A761E, A960E, A960F, AB60E, AB60F Oversized Main Pressure Regulator & Boost Valve Kit 147741-04K
  • A750E, A750F, A760E, A760F, A760H, A761E, A960E, A960F, AB60E, AB60F Oversized Main Pressure Regulator & Boost Valve Kit 147741-04K

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.

A750E, A750F, A760E, A760F, A760H, A761E, A960E, A960F, AB60E, AB60F Oversized Main Pressure Regulator & Boost Valve Kit Vacuum Test Locations