Rpms?
 

Just curious...what RPM should a 2008 2.4L be running at 55-60?

Depends.
Auto or 5 speed ? And what gear is it in.

Auto and I think third. I'm having shifting issues. I don't think it's going into low gear and not sure about high gear. Is it a 3 speed or 4?

4 speed; What issues, exactly. We may be able to help.

It seems to start out ok, shifts at 25-30 and then doesn't shift any more. Changed fluid and filter, changed the intake solenoid and the (I think it is called) Trans control module. I can drive it at 55-60 running at 2500-3000 RPM

Got a P/0100 error code

That means that there is a problem with the MAF circuit. Changed the air filter just before it came on?

Yes, it could cause trans problems.

2500 at 65 is about right.

No, I don't think we changed it...perhaps we should?

MAF Circuit...sounds like more research :)

RPM's sound about right...

My 06 2.4 is right about spot on at 2000 rpm going 55