I've heard the vague rumors of a gearing change on the 2.8 A6 for "00, and possibly on the '99.5. Possibly a change in the transmission software (if there is such a thing). Anyone out there with any solid information? Since the A6 and A4 share essentially the same engine, have the changes--if any there be--also affected the A4?

Changing the software will only change the behavior (shifting, etc) of the transmission. To drop RPM in a specific gear will necesitate physically changing the gear (cog ) itself, changing the number of revolutions the input shaft makes vs the output shaft. If anyone reads this, I would be interested in finding out if I can go with a lower (numerically higher) gear for 5th gear in my 99.5 18TSM. I would not mind dropping the highway RPM's down 500-800. I can always downshift if I need to pass.