The boost valve assembly is designed to increase line pressure in Drive and Reverse. When the Aisin AW 450-43LE sleeve is worn on the inside or loose within the valve body, boost or EPC fluids can leak to exhaust or cross-leak and increase forces on the valve. Leakage to exhaust reduces line rise, while the cross-leaks can result in broken clutch drums or cases. Sonnax main boost valve kit 94987-09K has upgraded materials to prevent wear and restore proper hydraulic control.

Sleeve is manufactured from highly wear-resistant billet aluminum
Hardcoat anodized aluminum valve combats premature wear
Restores proper hydraulic sealing and OE pressure control
Drop-in Zip Valve™ parts install quickly and easily

Learn More About Zip Valve™ Drop-In Repairs

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