[Dave in MN]

The loud "thud" is likely the radius ball pushing the socket assembly apart and the sound occurs when the socket reaches its limit.

The lower part of the socket is held against the ball by spring pressure. When the front drops into a pothole, and then climbs out, there is a tremendous amount of force being transmitted back to the radius ball and socket. The ball will try to move backwards and as it does the lower half of the assembly (moveable) fully collapses the springs and the nuts stop the movement. This will cause a pretty robust momentary force against the bellhousing and the resulting sound.

A full size and round ball will make the noise to a lesser amount. A worn ball will make more noise because the movement is greater within the socket. Just my observation.

Feeling it in the steering...Yes the movement described will place some momentary pressure on the pitman arm and that is felt in the steering wheel.

I heard this sound many times while driving parts of Route 66 in 2013 with my Phaeton. The old road was rough.

Good Day!