Product Description
O-Ring style. Kit can be retrofit to back to '89 units. See instructions for details.
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 34200-01K 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 valve
Symptoms
- Uncontrollable line rise
- High line pressure
- Broken parts
- Broken clutch piston
Cause
Worn boost valve sleeve allows reverse oil leakage and worn end plug causes imbalance of the pressure regulator valve.
Correction
Ensure proper regulator valve control with this O-ringed balance oil plug and boost valve & sleeve kit that replaces either the 1997-later or 1996-earlier OE boost valve designs.
Contents
- Valve
- Sleeve
- Sleeve O-Rings (2)
- Balance Plug
- Balance Plug O-Ring
