Important question. I just recently got a tj and am a bit confused if its driving properly. When i hit fifth gear and im going 55 to 60 the jeep is going over 2000 rpm. Is it supposed to be so high? or is it supposed to be like 1700 rpms at that speed. When i stopped at one light I could hear the engine accelerating by itself. Your help is greatly appreciated.
thanks  

You can check to see if your tires are properly inflated and to make sure that they are the same size as factory. Smaller tires would make your RPMs at speed higher, but then again your speedo would be off too.  

As for the engine accelerating by its self, if its just changing by  hundred rpm or so that could be due to the A/C compressor cycling on and off. if its revving by a thousand or more rpm you need to take it to a mechanic.  

What is done to the TJ? Lift? Tires? Gears? What engine and trans? 2000 could be normal, but we can't say for sure without a little more info...  

The jeep is stock. the only thing it has is 31 inch tires. But it has no other modifications