That's exactly what I thought was going on, I've never diagnosed one of my issues before and I don't want to go the mechanic throwing money around at things I don't know what I'm talkin' about.

But the brake booster vacuum wouldn't be causing all of those symptoms, would it?

I figure it'll probably affect the idle speed. grumbling and whistling, but would the vacuum affect my shifting too?

Or would it be almost like a chain reaction, where the problems fix each other like this:

vacuum -> idle -> shifting

Thanks again