Symptoms:

  • Erratic shifts
  • Soft shifts
  • Low line pressure
  • Low line rise
  • Clutch slippage
  • High line pressure in Reverse
  • Burnt clutches
  • High line pressure
  • Harsh shifts
  • Low converter pressure

Cause:

Continuous oscillation of the pressure regulator valve causes bore wear which results in line pressure deviation and valve instability. Reverse boost sleeve wear allows Reverse pressure and SLT oil leakage.

Correction:

Recover hydraulic control and renew performance by reconditioning the bore and installing the Sonnax oversized primary pressure regulator and Reverse boost valve kit.
  • U660E, U660F, U760E, U760F Oversized Primary Pressure Regulator & Reverse Boost Valve Kit 47740-02K
  • U660E, U660F, U760E, U760F Oversized Primary Pressure Regulator & Reverse Boost Valve Kit 47740-02K

You need this if...

Vacuum tests at the ports indicated fail to hold at least 18 in-Hg.

U660E, U660F, U760E, U760F Oversized Primary Pressure Regulator & Reverse Boost Valve Kit Vacuum Test Locations