I have had some vibration problems with my shift knob at high speeds and tha knob rattles like crazy... is there a damping sort of adhesive i can put on there so it's better bonded to tha shifter, thus vibrating less?
does the knob only rattle/vib, or is it the whole shifter assembly (i.e. does the handle/arm rattle too)? did the shift knob screw on nice and tight? im just confused, as usual. the shifter transfers any drivetrain vibes, so it is normal. the stock shifter had the rubber isolator in the handle for these vibes. now if it has gotten worse lately, it could be your balancer, DS, mounts, etc, depending upon when the vibes get worse. good luck.
Depending if it really is your knob, and not what Hissin was alluding to, I would suggest getting a low profile nut that is the same thread pitch as your shift lever, and use that nut as a jam-nut/lock nut. The pressure it will apply should keep it from rattling around. Works good for mine.
i would really get a knob that threads on tightly. i see a loose knob as a real safety concern. just me.