Vehicles with Toyota/Lexus A750E/F, A760E/F/H, A761E, A960E/F and AB60E/F 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. 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
• Hardcoat anodized aluminum valves combat premature wear
• Restores proper line rise
• Drop-in Zip Valve™ parts install quickly and easily