After what I think was a great review of our new C30 (93) there exists a slight vibration when motoring between 12 and 1700 rpm. Actually, it can be down right teeth rattling. I have looked and noticed that the stuffing box drips more than it should. Would this indicate a shaft alignment problem? Any suggestions would be helpful. Of course the dealer says, "just bring it by, we'll look it over for ya." Thankx Ya'll