In Toyota/Lexus A340E and A340F late-style units the OE steel Reverse, EPC and cutback boost valves wear the inside diameters of the cast aluminum boost sleeve due to continuous reciprocation as they provide biasing force to adjust main line pressure. This wear allows critical Reverse, EPC and cutback fluid pressures to leak or cross-leak, creating numerous drivability complaints and part failures.

Replacing the OE assembly requires matching the correct valve spool ratio (three-dot, two-dot or no-dot sleeve) to ensure proper line pressure. The Sonnax dual-ratio boost valve kit 97741-01K not only restores hydraulic integrity, but also provides for all OE ratios in one assembly. By selecting either the large diameter priority or small diameter priority EPC boost valve and adding optional shims to the OE pressure regulator valve spring face, all three of the OE ratios can be achieved with the one assembly.

• Sleeve is made from high-quality aluminum for wear resistance
• Hardcoat anodized aluminum valves combat premature wear
• Unique priority diameter design allows for dual-ratio in one assembly
• Additional shims allow for tuning to the third OE ratio
• Drop-in Zip Valve™ parts install quickly and easily