If the shaft/grip combo ends up being either lighter or heavier than your current shaft/grip combo, then yes you will probably need to use a different TS Surefit weight than the one initially installed. The question is what swing weight are you trying to achieve with the new shaft/grip? If you are unsure about about which weight to use then you should consider consulting with a qualified fitter...preferably a Titleist fitter.

I want to end up with a D4 swing weight which is the value used in the club fitting . I don't yet have the completed club (head and shaft combination), so I don't know what the "current" swing weight will be. I will have access to a swing weight scale so I should be able to determine the appropriate TS weight to achieve D4 or as close as I can get to it.