Ok, you vehicle is in what is called Limp Mode. This allows you to at least get the vehicle somewhere to have it checked.
If it is a 4 speed then there are a couple Shift Selenoids inside the tranny on the Valve Body. One or both may have broke. To check this you can remove the Tanny Pan. Here are a couple pics.....
1st 2nd Shift
Lock-up, 3/2 Shift
Monday, June 16th, 2008 AT 3:27 PM