Common problems in vehicles with GM 4L80-E and 4L85-E transmissions are uncontrollable line rise (upward of 500-600 psi), high line pressure in Reverse, buzzing noise, broken direct clutch drums and/or broken cases. These problems are usually caused by reverse boost oil that enters the torque signal circuit due to a wear-created cross leak at the sleeve. High line pressure and buzz is created by oil leakage past the aluminum balance plug. The Sonnax boost valve kit S34507RDK eliminates these problems. Hardened steel boost valve has over 20% wider spools to provide better durability and increased sealing contact area; Boost valve spools have annular grooves to reduce side loading that causes wear; Quality steel boost sleeve with external O-rings provides positive seal to compensate for pump cover bore wear; Kit includes a replacement aluminum balance oil plug with an O-ring to ensure proper sealing and adequate back pressure on the pressure regulator valveDrop-in Zip Valve™ parts install quickly and easily
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Sonnax 34200-01K Transmission Boost Valve & Sleeve Kit (Includes O-Rings)

Sonnax 34200-01K Transmission Boost Valve & Sleeve Kit (Includes O-Rings)

Transmission Info

4L80E:Boost Valve & Sleeve Kit (Includes O-Rings) 1991 - 2018

Other Product Numbers

  • 348-5410
  • 34200-01K
  • 3420001K
  • 34507RDK
  • K34968D
  • S34507RDK

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