Hi all,
Thanks for all the replies. It's great to know that it sounds normal and I probably have nothing to worry about. I guess I'll drain the fluid to look at the color and fill it with new fluid.

To Blacksambo: what grease do you use to lubricate the shaft? What other maintenance I should better do on it other than changing transmission oil and lubing the shaft at 55K miles on my 99 VX? I don't know what has been done on it before so let's consider that nothing has been done other than changing oil.

To AK Falco: - are you the guy who bought that silver VX that was for sale in Everett WA? If you are - then I'm that other guy who finally made it to Everett to take a look at that VX when you were buying it. Thanks for the link to the clunk tranny sound.