When shift codes and shift complaints such as harsh shifts are found in Toyota/Lexus A750, A760, A960 and AB60 series units, the accumulator control valve is frequently the culprit. Worn components in the accumulator control valve train allow cross leaks between hydraulic circits and pressure losses to the sump. Installing Sonnax oversized accumulator control valve kit 147741-24K will eliminate cross leaks and uncontrolled pressure loss.

• Restores OE accumulator control valve function
• Hard-coat anodized aluminum provides wear resistance
• Sleeve is manufactured of highly wear-resistant aluminum alloy

Toyota A750E/F transmissions may exhibit poor shift quality due to wear in the clutch control bore. The clutch control valve controls clutch apply and release rates. The wear is typically visible upon inspection of the valve and bore. The Sonnax oversized clutch control valve kit 147741-22K allows the bore to be refurbished and the hydraulic integrity of the circuit to be restored.

• Oversized, hard-coat anodized valve is manufactured to extremely tight tolerances and resists wear
• Salvages previously non-repairable worn valve bodies and avoids expensive valve body replacement castings

The continuous oscillation of the secondary pressure regulator valve in Toyota/Lexus A750, A760, A960 and AB60 series units wears the valve spools and valve body bore at the contacting surfaces. This wear results in TCC pressure irregularities and valve instability. If pressure is high, harsh lockup clutch engagement can result. If the pressure is too low, the TC clutch cannot achieve complete lockup. Continuous clutch slippage will lead to burnt clutch material and converter. Under these conditions, loss of mileage and poor drivability are to be expected.

Sonnax oversized secondary pressure regulator kit 147741-10K includes a high-quality steel valve with annular grooves to reduce side load wear and extend valve and valve body life. Sonnax tool kit F-147741-TL4 was designed as a multipurpose tool. Used in conjunction with our VB-FIX reaming fixture, both the main pressure regulator bore and the secondary pressure regulator bore can be reamed and prepared for their respective kits: 147741-10K and oversized pressure regulator and boost valve kit 147741-04K.

• Valve is made from high quality, hardened steel to resist wear
• Inner spool has annular groove to reduce side-loading

Toyota vehicles equipped with listed transmissions frequently exhibit TCC and lube/cooler flow problems due to excess wear in the lockup relay valve bore. This bore deterioration allows vital fluid loss, often resulting in TCC apply and release concerns, TCC codes, lube failures, overheating, and burned TCC lining. Reconditioning the bore and installing Sonnax oversized lockup relay valve kit 147741-07K shores up the hydraulic integrity of these circuits, restoring normal TCC/cooler/lube function.

• Hardcoat anodized aluminum valves combat premature wear
• Matched spring helps restore OE performance

Toyota vehicles equipped with listed transmissions may exhibit driveability problems caused by erratic oil pressure delivered to various solenoids. Low cooler flow, solenoid codes, impaired TCC operation, and various shift concerns are common results of this abnormal pressure. As the OE solenoid modulator valve oscillates and strokes over time, bore wear occurs that prevents proper regulation of solenoid supply pressure, flooding or starving the solenoids and causing erratic solenoid operation. Reconditioning the bore and installing Sonnax oversized solenoid modulator valve kit 147741-05K shores up the hydraulic integrity of this circuit for renewed solenoid performance and trouble-free shifting.

• Hardcoat anodized aluminum valve combats premature wear
• Annular groove helps center valve in bore to reduce future side-load wear

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

Toyota/Lexus vehicles with A750, A760, A960 and AB60 series transmissions may exhibit insufficient line rise in drive ranges and excessively high pressures in Reverse. This may be caused by continuous oscillation of the steel boost valves within the cast aluminum sleeve, creating excessive wear and a path for EPC, cutback and Reverse pressure to leak.

Severe wear at the reverse circuit allows line pressure to cross leak to the EPC circuit, causing abnormally high pressures. Wear in the cutback circuit allows fluid to cross leak into an exhaust circuit, causing low line pressure resulting in soft shifts and band failures. The Sonnax boost valve kit 147741-01K has upgraded materials and minimal clearances to prevent wear and restore proper hydraulic control.

• Boost sleeve is manufactured from highly wear-resistant billet aluminum to prevent the excessive wear exhibited by the cast OE sleeve
• Restores proper line rise