February 21, 2013
The OE pressure regulator valve design prevents adequate cooler flow at low RPM and high pressure/demand conditions, which can create overheating. Additionally, in '99-later vehicles, the factory EPC pressure was set high at idle, resulting in engine surge conditions in GM 4L80-E and 4L85-E units. Sonnax lube regulated pressure regulator valve 34200-14K provides a significant increase in cooler flow under low RPM and high pressure conditions that benefits all vehicles, and eliminates the need for reprogramming '99-later vehicles with high EPC pressure at idle. The replacement pressure regulator valve has an encapsulated check valve that allows regulated flow to the converter charge/lube circuit at vehicle idle.
Sonnax valve body layouts provide a detailed overview of individual units making it quick and easy to determine what’s available for the specific valve body you’re working on. See all Sonnax valve body layouts.
Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.