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Brand: Sonnax

Other Part Number: S104741R-1

Type: Valve Body

Interchange Part Number: S45741GK

Items Included: Oversized Clutch Boost Valve

Manufacturer Part Number: 104740-01

Material: Aluminum

Universal Fitment: Yes

Vintage Part: No

Performance Part: Yes

6L45, 6L50, 6L80, 6L90

Oversized Clutch Boost Valve
Part No. 104740-01

Fits any of 3 locations

Tooling Required:
  • F-104740-TL
  • VB-FIX
GM 6L45, 6L50, 6L80 and 6L90 clutch boost valves provide feedback pressure to their respective clutch regulator valves, balancing the regulators to assist with apply and release of the associated clutch. Pressure control solenoid fluid acts on the boost valve to precisely control the amount of oil delivered to the balance end of the clutch regulator valve. Excess wear in boost valve bores can result in harsh shifts, slipping, burnt clutches, flares, codes, and delayed engagement. Reconditioning the bore and installing Sonnax oversized clutch boost valve 104740-01 restores the hydraulic control necessary for trouble-free shifting.

Proper operation of clutch boost valves depends on correct pressure being supplied by shift solenoids. If trouble is found with pressure supply to these solenoids, Sonnax offers oversized AFL valve 104740-12.

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

This valve is packaged individually, but can be used in any of three bore locations:

  • "B" Stamp: 4-5-6 Clutch Boost Valve
  • "F" Stamp: 3-5 Reverse Clutch Boost Valve
  • "K" Stamp: 1-2-3-4 Clutch Boost Valve

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