I took the car out this morning and the transmission is stuck in 3rd gear when it's in drive. Park, Reverse and Neutral work fine. It starts from 3rd and won't shift into overdrive or downshift. I have no idea what this could be, probably some sort of an electrcial problem. Any help would be greatly appreciated! Thanks everyone

 

that's the "limp home mode"
there's somethign wrong with your tranny.. if you didn't do anything beforehand (like excessively spinning your tires in the snow or something), then it's probably about tiem for that tranny to spend a day in the shop with a competent mechanic.
that's your tranny crying for help. so help it.

 

Damn, it just snowed yesterday, spun my tires a little bit but not huge. It has been doing it intermittentley for a while now but never constant. This tranny's only got like 30,000 on it. Don't know much about transmission problems, is this electronic or mechanical in the tranny? Thanks Matt