Do you still have it? Can you post a pic up against a ruler?

 

Okay i bought my trans am about 3 months ago and i dont wanna sound like a moron or anything but im not real good with trannys. I bought the car and looked everything over. Started driving the car for about 2 days. Tranny locked up. come to find out there was no tranny fluid. So i had the tranny rebuilt. Put it in a few days ago and i started it on the lift and ran it threw all the gears. Shifted perfect. Drove the car and when the car started to get hot the trans didnt want to go into third gear. 1st to 2nd shift fine. 2nd to 3rd it wont go without alot of force. But it will go 3rd to 2nd just fine. and the rest to. I dont know what the problem is.. anyone have any suggestions?

 

You should check your fluid level first. Maybe the case is leaking? If you still have problems, you should start a new thread on the site for your specific issue if you can't find anything in a search.