Symptoms:

  • Reverse band failure
  • Rear servo bore wear
  • Forward clutch failure
  • Delayed Forward clutch

Cause:

Heavy scoring at the case bore for the inner piston seal allows drive oil loss, which can cause forward clutch and/or reverse band failure.

Correction:

Sonnax drop-in reverse servo sleeve kit restores the function of the reverse piston and salvages the case.

4R44E, 4R55E, 5R44E, 5R55E, A4LD, C3

Reverse Servo Sleeve Kit
Part No. 56532-01K

View Instructions Find a Distributor

The reverse servo bore found on the case of listed Ford transmissions can become scored due to repeated oscillation of the reverse servo piston within the bore during normal operation. Once this bore is damaged, the case must be scrapped. Install the Sonnax reverse servo sleeve kit 56532-01K to refurbish the case bore. The drop-in Zip Valve™ installs quickly and easily.

Learn More About Zip Valve™ Drop-In Repairs

Instructions are included for machining the servo piston assembly by simply turning the smaller piston journal 1/16" smaller.

  • Sleeve
  • Back-up Ring
  • O-Ring
  • 4R44E, 4R55E, 5R44E, 5R55E, A4LD, C3 Reverse Servo Sleeve Kit 56532-01K
  • 4R44E, 4R55E, 5R44E, 5R55E, A4LD, C3 Reverse Servo Sleeve Kit 56532-01K