96 tranny shiftin problems

ok i got my 1996 3.4 3 weeks ago and when i drove it , it would randemly shift all the time and the speedo would move all over the place, say im going 30 mph it would move between 15 and 50 mph, so i went under the hood looked at some things and then it all stopped it shifted fine speedo was fine for about a week. first day i took it on the freeway it was fine, then 2 days ago i took it on the freeway 20 mins in and the speedo drops to 0 and the trans starts slipping so i had it towed home. i took it for a drive yesterday and it wont shift from first and the speedo dont work. any ideas? im 18 and good with a wrench. i need to fix it asap

Seems the shifting problem goes with the speed info problem. Computer confused.
I'd check first for wiring/connectors starting at transmission speed pickup, near passenger side transaxle housing, near shaft output.
www.avigex.ca/xport/4T60pickup.jpg
www.avigex.ca/xport/speedsensor38.jpg

thanks it helped i found wiring going to the speed sensor that was bare i taped it up and its now working fine

Well its not working again i got a p1441 with a p and upside down p and p0756 also p0756 with p and upsidown p what's going on is I don't have first need to fix any ideas? Thanks