Here we are at day 4 and the noise is still gone. I haven't driven the car much, just around town. It probably has 300 miles on it since the cv joint stopped making noise.
On Monday I had a long talk by phone with Steve at CVJ and he tried to explain to me how the cv joint works and what might go wrong inside. I would have understood much better with a diagram in front of me but I guess one of the little steel balls or one of the plastic clips in the cv joint must have gotten pushed out of place and was getting hit by something else in the joint to make the noise. It then must have popped back into place or fell out completely, so the noise stopped.
I suspect that I'll put the replacement axle (should arrive UPS today) in the trunk and drive back to California with the "bad" one in the car. Steve says that the axle will last for many miles even after it starts making noise. If I make it home noiselessly I'll probably return the axle to CVJ and find some other noise to worry about.
Also, thanks for the comment on shocks, kraut, it is indeed a common failure mode. Mine were replaced with stock Bilsteins a little over a year ago.
Jeremy
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"Buster" in the '95
Our all-Diesel family
1996 E300D (W210) . .338,000 miles
Wife's car
2005 E320 CDI . . 113,000 miles
My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970