As an experiment, Loosen one of the bolts that hold the carrier bearing to the body and remove the other. Put a washer between the carrier and the body so that you can put the bolt that you removed back through it.

See if this helps. This will put the u-joint in a SLIGHTLY different position away from the "notch" that normally wears into it.

While under there check to see that all motor, transmission and differential mounts are tight. You may need to pry around with a long bar to check them.