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