124 Tranny Lunka Lunka?

[dwighthinton]

I have owned a 1992 500E for the past 10 years. Now 145K miles. Still Love it. However, I continue to be curious about a mild condition that also existed in my wife's 124 300E. Occasionally, when decelerating... i.e. below 40 mph, the car experiences a mild surging which I call "lunka lunka". It is similar to trying to idle along in an old stick shift car at 5 mph in top gear...it sort of tries to lunge back a forth a bit... cannot reproduce it in front of my friend an MB mechanic. Does not matter which gear is selected...even does it in reverse...Most noticeable below 10 mph creaping along in traffic but it is still an infreqent occurrence.

Has anyone heard of this? Any idea what causes it?