Jaguar ZF6HP-26 rebuilders must use care Recently the ZF6 converter, found in the 2003 Jaguar S-type, found comfort in a revolving door of rebuilders’ shops around the country. Since it’s 2003 arrival, problems including premature clutch failure, harmonic vibrations and loosening converter bolts have plagued rebuilders.
Randy Miller, owner of European Auto Repair, has fallen victim to repeated torque converter failures surrounding this converter. Until this time, the only choice for Miller was purchasing factory new converters from Jaguar to solve his customer’s complaints.
For those who are unaware, the ZF6HP falls into the same category as other ZF5 converters using the captive clutch design. This type of unit uses the weld-in-place method of clutch retension. Do not attempt to rebuild this converter without removing the clutch assembly. The clutch plate is usually worn and unusable. This is a excellent place for debris to collect and hibernate. Removal of the piston requires a precision lathe cut with approximately a .050” parting tool. A groove is cut on a diameter of 2.930” +/- .010”. Use caution here, as this is a critical incision. Do not machine into the 3 machined holes located next to the machined groove. See top photo. Care must be taken not to damage the O-ring, shown in green in the photo to left, during reassembly. When welding the piston into place, be sure to relocate it to its original height. If material is removed from the clutch mating surface on the front cover, it must be replaced by a spray welding process to build up the lost material. Remachining of the welded surface will provide the perfect clutch clearance. This should be simpler than it sounds. Contact Dennis at (800) 554-2668 for more information.
– Found in July 2006 Newsletter