• Engine surge at idle
  • Low cooler flow
  • Low TCC release pressure


Low converter release pressure at idle.


The Sonnax replacement pressure regulator valve allows regulated flow to the converter charge/lube circuit at vehicle idle, while preventing converter or pump drainback.

4L80-E, 4L85-E

Lube Regulated Pressure Regulator Valve
Part No. 34200-14K

You need this if... View Instructions Find a Distributor

The OE pressure regulator valve design prevents adequate cooler flow at low RPM and high pressure/demand conditions, which can create overheat complaints. Additionally, in '99-later vehicles, the factory EPC pressure was set high at idle, resulting in engine surge conditions in GM 4L80-E & 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.

  • Replacement pressure regulator valve has an encapsulated check valve that allows regulated flow to the converter charge/lube circuit at vehicle idle
  • Check valve prevents converter or pump drainback
  • Improves converter release pressure
  • Prevents engine surge at idle in'99-later vehicles

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  • 34200 14k combo
  • 34200 14k

You need this if...

Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.

  • 34200 14k in