Symptoms:

  • Engine stall on engagement
  • TCC apply concerns
  • Broken sleeve
  • Low line pressure
  • Low boost pressure

Cause:

The cast-aluminum sleeve breaks at the retainer area due to sleeve porosity and the retainer cocking in the bore and exerting excessive force on the thinnest part of the sleeve.

Correction:

The drop-in billet aluminum sleeve provides higher tensile strength and reduced porosity to resist breakage.

450-43LE

Cutback Valve Kit
Part No. 94987-01K

Fits '98-later models: Isuzu NPR, GMC Forward Tiltmaster, Chevrolet Forward, Nissan UD and Mitsubishi Fuso Trucks.

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The cast-aluminum cutback valve sleeve in Aisin AW 450-43LE units breaks at the retainer area due to sleeve porosity and the retainer cocking in the bore and exerting excessive force on the thinnest part of the sleeve. This allows the valve and sleeve to move out of position and can create engine stalls when put in gear. It also allows the lockup control valve to move out of position, which can create converter apply issues. Broken pieces of the sleeve can end up in the pan, break into smaller pieces and clog filters or lodge in moving components.

The Sonnax billet aluminum cutback valve kit 94987-01K provides higher tensile strength and reduced porosity to resist breakage.

  • Billet aluminum sleeve provides higher tensile strength and eliminates breakage
  • Improved valve and sleeve materials prevent wear and provide better sealing capacity through temperature changes
  • A replacement spring has also been provided, to maintain OE calibration
  • Drop-in Zip Valve™ parts install quickly and easily
Learn More About Zip Valve™ Drop-In Repairs
  • Sleeve
  • Spring
  • Valve

Sonnax valve body layouts provide a detailed overview of individual units making it quick and easy to determine what’s available for the specific valve body you’re working on. See all Sonnax valve body layouts.

Aisin AW 450-43LE Valve Body Layout

Aisin AW 450-43LE Valve Body Layout
  • 450-43LE Cutback Valve Kit 94987-01K
  • 450-43LE Cutback Valve Kit 94987-01K