whats in the tranny

hi there, im having tranny problems, a bad sensor the dealer told me, but i dont have the $$ to fork over for dealer to check and install new tranny sensors, so my question to you is, do you know what the sensors on the 2g eclipse tranny are called, and where i mihgt be able to get them cheaper than a dealer, e.g. pepboys or sumptin... thanks for any help u can give me

-nolan