45-RFE converter causes havoc among rebuilders

The 45-RFE torque converter, which is found in many 2000 and newer Chrysler vehicles, is becoming quite troublesome for many rebuilders. Issues including leaks, vibrations and miscellaneous problems are appearing after rebuild.

Even the most experienced rebuilders encounter numerous comebacks and are seeking a resolution to these problems.

First, the leaking impeller hub will be addressed. Many times after careful examination, rebuilders find an existing crack located at the impeller hub joint (see photo directly below). In most cases this seems to be due to an inadequate factory weld during manufacturing. Some rebuilders, as a precaution, will reweld the existing impeller hub where the crack exists (see smaller photo below). Minor machining is required after this procedure; however, a more stable repair is to replace the impeller hub with a new replacement hub available from your parts supplier, such as Sonnax or Tri-Component. This hub is furnished as a flanged unit only, and it does provide the rebuilder a generous welding surface.

Second, vibrations steming from uneven clutch application, which can usually be caused by a worn clutch conical and/or sealing rings, are also causing rebuilders problems. Replacement of the conical and sealing rings are recommended to assure proper clutch function.

In addition to replacing the parts mentioned above, blast-beading or chemical striping the OEM clutch liner from the clutch piston instead of machining the clutch piston on a lathe will prevent thinning of the clutch. Proper bonding procedures must be followed carefully to prevent delamination. Be sure to use a high-quality replacement-type friction liner, preferrably a high-carbon component.

This converter contains two Torrington roller bearings. It is suggested to replace both bearings at the time of rebuild. This will prevent a possible return due to bearing fatigue. Even the best rebuilder cannot predict the life of a roller bearing based on its exterior appearance. Most of these converters have more than 80,000 miles of use, and it is best to replace the bearing now rather than rebuild the entire unit later.

A third area of concern should be proprer balancing of the unit. If proper alignment tools for the balancer being used are not used, it is suggested to purchase them before attempting this rebuild. Critical balancing alignment is required to ensure a smooth operating converter. The 45-RFE converter needs to fall within 10 grams of the balancing specifications to maintain the pump bushing’s integrity.

By following these recommendations, the 45-RFE should no longer cause constant comeback concerns.

– January 2007 newsletter  issue