1996 Grand Voy., 3.8L engine, tranny prob. -HELP!

[Timinator2000]

Hello everyone.

Can someone tell me if I'm into big bucks?
Here's what happened:
I was travelling at a fair speed ..80km approx.. and when I come to slow down at a set of lights, I felt the tranny shift hard into 2nd. Once it did that, I no longer had 3rd gear... I pulled over, restarted the engine to kick myslef out of limp mode and tried to drive again.. after doing about 50kms, the 3rd gear shifted but no transmission.. instead the enging just reved up to 3000, came back down and second gear kicked back in and the vehicle went back into to limp mode... I pulled over again and checked my fluid.. it was low so I put som tranny fluid in .. same results.. I have read posts that mention to change the fluid and the filter.. is it worth a try or am i wasting my time.. I have never changed the fluid nor filter on my van.. If the tranny fluid was low, did I just cost myself a 3000 tranny repair?? HELP!

Thanks for any reply!

Tim.