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Sonnax 34910-01K Transmission Reverse Boost Valve Kit (Includes O-Rings) TH400

by Sonnax
SKU S34507RK
Original price $29.17 - Original price $29.17
Original price
$29.17 - $29.17
Current price $29.17
in stock, ready to be shipped

Delivery time

You will receive your package in 2–5 business days within the contiguous U.S.

Brand: Sonnax

Other Part Number: S34507RK

Type: Line Pressure Boost Valve

Interchange Part Number: S34507RK

Items Included: Boost Valve and Sleeve Kit

Manufacturer Part Number: 34910-01K

Material: Steel

Universal Fitment: Yes

Vintage Part: No

Performance Part: Yes

TH400, TH425 Transmission Pump

Boost Valve Kit
Part No. 34910-01K

O-Ring Style

Vehicles with a GM 400 and 425 transmissions frequently have poor line rise, soft 1-2 and/or 2-3 shifts and/or Reverse engagement difficulties. These problems can be caused by the reciprocating boost valve wearing the I.D. of the boost sleeve. When this occurs, oil that enters the modulated throttle valve orifice leaks past the boost valve and exhausts through the Reverse orifice or to the sump, resulting in poor line rise. Reverse oil also can exhaust both to the sump and back through the modulated TV orifice. The O.D. of the boost sleeve also allows some leakage through the pump body, which can increase boost oil loss. Sonnax boost valve kit 34910-01K eliminates the above problems by restoring hydraulic integrity and providing a positive seal with the pump bore.

  • Valve and sleeve manufactured from high-quality steel
  • O-Rings provide additional protection against leakage through the pump body to assist in maintaining pressure in the circuits which supply the boost valve
  • Uses the same valve spool diameters as the OE version to retain factory shifts
  • Valve
  • Sleeve
  • O-Rings (2)

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