Symptoms:

  • Clutch distress
  • Low line rise
  • Reverse slip
  • Chatter in Reverse
  • Shift quality gets worse as temperature increases
  • Flare shifts

Cause:

The pressure modulator valve controls accumulator back-pressure, relative to load and boost pressure. Bore wear will not allow a rise in accumulator pressure. Slippage and clutch failure are the result of poor line rise.

Correction:

Restore roundness, concentricity and finish by oversizing the bore, then finish the restoration by installing this Sonnax oversized pressure modulator valve kit.

ZF5HP19

Oversized Pressure Modulator Valve Kit
Part No. 85755-03K


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

In ZF5HP19 units, the pressure modulator valve train controls accumulator back-pressure relative to load and is subject to significant wear due to constant motion under normal operating conditions. Excessive bore and valve spool wear will likely cause poor or no line pressure rise. Poor line pressure rise is indicated by flare upshifts or slip/chatter in reverse. Other symptoms such as softening and lengthening shifts with rising temperature and clutch distress may be present. Installing Sonnax oversized pressure modulator valve kit 85755-03K can restore proper functionality to the entire bore and valve train.

  • Valve is hardcoat anodized
  • Valve is manufactured to extremely tight tolerances

OE valve spool diameters must match dimensions noted in the illustration. This kit cannot be used to repair valve bodies with valves of other sizes.

  • Pressure Modulator Valve
  • Piston Valve
  • End Plug
  • ZF5HP19 Oversized Pressure Modulator Valve Kit 85755-03K
  • ZF5HP19 Oversized Pressure Modulator Valve Kit 85755-03K
  • ZF5HP19 Oversized Pressure Modulator Valve Kit 85755-03K details

You need this if...

A vacuum test at the ports indicated fail to hold at least 18 in-Hg

ZF5HP19 Oversized Pressure Modulator Valve Kit Vacuum Test Locations