Screw you, Houston

So my car needs to go into the shop.

That sentence sounds so simple until you break it down. Why does it need to go into the shop? It makes a growling noise when it hits speeds above 30 m.p.h. That's as specific as I can get. I don't know why it makes that noise (Tex suggested bad bearings, SB thinks it might be the exhaust system or something that starts with T that I can't remember [not transmission]), so I don't really know what kind of shop I need to take it into.

Second, I'm really resistant to taking it in during normal working hours, because I don't have any way to get to and from work. Or at least not any convenient way.

So if you have any advice for me and my Tracker, please fork it over.

Thanks.