[gouldie1903]

is the check engine/transmission light on?

and is it an electronicly control transmission?

i had a similar situation where it would only drive in 3rd but reverse worked. it was the computer's safe mode because i blew the fuse to the tranny controler.

if it isnt a computer controled tranny take off the fluid pan pan and see if there are any debris on the bottom.

hopefully it isnt something major
good luck,

chris