When merging on to the interstate my car accelerates smoothly all the way up to about 5k rpm then it pauses there for roughly 2 secs and sometimes 3 secs then shifts. But it will not rev past that point unless I'm in park or neutral. I'm not trying it in reverse though lol.

About 3 months ago there was a small hole in the little hose near the oil pressure sensor that was squirting out transmission fluid. So I replaced it and kept adding half a quart at a time and drove around my neighborhood a few times until it was full.

 

pull codes. i would assume there is a code if it wont rev past 5k

 

Today I went out to test it a little more and the problem only exists when the the engine and transmission are hot.

Codes:
P0011 Intake Valve Timing Control Performance Bank 1
P0550 Power Steering Pressure Sensor Circuit Malfunction

2003 5at just a ztube

 

Had P0011 issues with my '02 Maxima, sometimes its the cam position sensor, sometimes the solenoid, never was able to figure mine out. But if I managed to over rev the engine and hit the limiter (usually accelerating on cold pavement would spin the wheels if I wasn't careful) and it would put my car in limp home mode. I'd have to pull over, turn the car off for 30 seconds, then restart it before it would drive normally again. Not like your issue though, with mine it was running fine or limp home mode, sounds like you have something in between.