sonnax-black Facebook-color LinkedIn-color maillink printlink r_and_r_only SERVOFIX-logo-web Twitter-color VBFIX-logo-web video-logo-web warranty_only Youtube-color


  • High line pressure
  • Low line pressure
  • No line rise
  • Delayed engagement
  • Converter concerns
  • Engine stall at idle


Constant oscillation of the main regulator valve and/or the boost regulator valve in their bores creates wear, which can result in oil pressure loss or cross leaks and valve malfunction.


Sonnax now offers an oversized valve kit for both the main regulator valve and boost regulator valve to restore proper clearance to the bore and prevent oil loss.

096, 097, 098

Oversized Main Pressure Regulator Valve Kit
Part No. 119940-08K

View Instructions

If regulated line leaks to exhaust at the main regulator, it creates a low pressure condition. Wear at the inner balance spools prevents the valves from stroking, which can cause high line pressure. Wear at the inboard bore also affects the K1 clutch circuit, which can result in 1-2 or 2-3 shift complaints. Wear at the inboard end of the boost regulator bore can reduce the ability of EPC/TV pressure to stroke this valve open. Full boost exiting this valve combines forces with the main regulator spring, increasing line pressure. Sonnax offers an oversized valve kit for both the main regulator valve, 119940-08K, and the boost regulator valve, 119940-07K. These kits allow the valve bores to be refurbished and restore proper pressure control.

  • Oversized hard-coat anodized valves are manufactured to extremely tight tolerances and resist wear.
  • The main regulator valve kit contains an o-ringed end plug to positively seal the bore and prevent regulated boost line pressure from exhausting.
  • A new spring is included to work with the oversized valve and re-establish OEM regulated pressure specifications.
  • A replacement ratcheting end plug is included in the boost regulator kit, as the OEM one often breaks.
  • An adjustment tool is provided in the boost regulator tool kit for repeated assembly, disassembly and adjustment of the ratcheting end plug.
  • Valve
  • Spring
  • End Plug
  • O-Ring
  • Retainer

September 30, 2005

Anatomy of a Transmission: Oil Flow in the Pump-PR-Converter-Cooler Lube Circuits

Gregg Nader

Topics: Diagnostics And Theory Transmission

Read Now
  • 119940 08k combo
  • 119940 08k