Unregulated EPC pressure forces pressure regulator into high line position.
This self-regulating reverse boost valve regulates EPC pressure to 95-105 psi with an encapsulated relief valve.
Common problems in vehicles with a 4L80-E transmission include uncontrollable line rise (upward of 500 psi), high line pressure in reverse, broken direct clutch drums and/or broken cases. These problems can be caused by excessive EPC torque signal pressure. The Sonnax self-regulating reverse boost valve 34200-10K eliminates these problems by limiting EPC pressure.
Kit includes instructions to retrofit parts dating back to 89.
February 21, 2013
Topics: Vacuum Testing Vacuum Test Guides Transmission GM 4L80-E TransmissionRead Now
Contact a Sonnax Parts Distributor.
Wet Air Test can be done using either the reverse boost orifice or the torque signal orifice for this particular application.