my 3.90s should bee done...

I can't wait to get my baby back, today the 3.90 gears shpuld be awsome, II'l let everyone know how they are.Also how big of a difference will it be if they change my tranny fluid because I had them do that to?

Changing the tranny fluid could loosen up any binding that you may have been experiencing before the fluid change. Smoother shifts. If you were having tranny problems before and you still have them after the fluid change, you should have it looked at.