When I have my car in overdrive and I hit the gas, it has poor power and acceleration, but when I do it in drive, it has much better response. Also, when I'm driving in overdrive, the car surges back and forth a little, the RPMs jump about 250 to 500. I've had it slip out of gear when I was flooring it in overdrive a few times, it would get to about 5k RPMs, then the car would coast and the RPMs would shoot up. It doesn't do this in any other gear but overdrive.

 

Overdrive is not for acceleration. It is for hi speed cruising at less than full throttle, for gas mileage and less wear.
If you floor the gas petal it will shift out of overdrive into 3rd and unlock the converter. There is probiabily nothing wrong with your trans. But if you keep beating on it there will be. Go easy on overdrive and you and it will live a lot longer....

 

I was just flooring it to test it to see what was wrong. It has the rpm jumping, and I was flooring it to check other problems, and apparently when it gets to 5k rpms or something it slips out of gear and likes to jump into neutral or some bs. I have no clue what's up. Some help with that would be nice. Thanks for the info on overddrive and flooring though...wasn't sure what was up (even though it accelerated faster before).