September 30, 2005
Sonnax Zip Kit 4R44E-5R55E-ZIP targets the root cause of multiple complaints by sealing the critical circuit pressure losses in the Ford 4R44E, 4R55E, 5R44E and 5R55E valve bodies. The kit contains uniquely designed parts to prevent the loss of pressures within the main line, EPC, solenoid feed and converter circuits. This kit also includes modifications that provide firmer shifts, improves intermediate servo and direct clutch pressure, and improves TCC apply. The kit also seals multiple circuits known to suffer from end plug leakage or poor checkball sealing. No special tools are required for installing these parts.
The Zip Kit quick guide provides clear and easy instructions on one sheet to get the unit sealed up and back on the road fast. In addition to general rebuilding tips and technical information, the technical booklet included in this kit contains vacuum testing and additional repair options for higher mileage units or for repairing specific complaints which are beyond the scope of this kit.
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.
It's easy to restore and extend vehicle shift quality with Zip Kits. Uniquely designed, drop-in Sonnax parts target the root cause of valve body complaints and stop critical circuit pressure losses in the most common problem areas of the transmission.