Symptoms:

  • Soft shifts
  • Poor shift quality
  • Low base line pressure

Cause:

Worn, tired OE pressure regulator springs or aftermarket springs with higher spring ratings.

Correction:

The Sonnax elevated pressure main pressure regulator springs are designed to provide an effective baseline pressure. The slight increase in spring pressure compensates for wear elsewhere in the transmission.

4R44E, 4R55E, 5R44E, 5R55E

Elevated Pressure Main Pressure Regulator Spring
Part No. 56947-17

Package Quantity: 20

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The OE springs in many Ford transmissions wear or become fatigued, causing low baseline pressure. OE replacements are hard to find, and many aftermarket springs have unacceptably high spring rates. The Sonnax elevated pressure main pressure regulator springs are intended to provide a minimal baseline pressure increase (approximately 10 psi over OE baseline pressure), enough of an increase to help restore full line pressure. The springs may be used to replace worn OE springs and also to correct low line pressure caused by worn transmissions.

  • Highest quality spring material
  • Designed to gently exceed OE spring rates
  • Manufactured to tight tolerances
  • Drop-in installation requires no modification
  • Saves time looking through cores for replacement springs

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.

Ford 4R44E, 5R44E, 4R55E, 5R55E Valve Body Layout

Ford 4R44E, 5R44E, 4R55E, 5R55E Valve Body Layout
  • 4R44E, 4R55E, 5R44E, 5R55E Elevated Pressure Main Pressure Regulator Spring 56947-17