2008 f250 6.4L, No reverse and no overdrive, little power in all other gears but seems to shift fine once it decides to move. Have to rev engine to around 2k rpm. Before it will lock in then you can ease off and go down the road. Will throw itself back into neutral if you drive to aggressively. Transmission fluid looked great when drained and no metal shavings in the pan. Faint high pitched ring coming from EGR when truck is off sometimes, doesn't do it always. Also, I believe something is drawing batteries down. I plan on replacing the egrt sensor and going from there seeing as that is the only code as of now. Any other ideas of what may be causing this? This is the first time I've dealt with a situation such as this so any help would be greatly appreciated!

 

How old are the batteries?

 

batteries are ok. Removed both of them and checked them individually. I believe something in the EGR system is pulling them down

 

I haxd this code it was an egr temp sensor #1. It will put truck into limp mode. It is reading the the egr exhuast gas is too high and will put it into limp mode.

 

Replaced egr temp. sensor which eliminated the code. Same issues still occurring, Checked erg valve and it was completely blocked. Ordered a full erg delete kit and installed. same issues still occurring but now is not throwing any codes what so ever. Has to be transmission related at this point i believe. Reverse, first, and second will not engage. third on up shifts fine. possibly line pressure control solenoid? Also truck acts like its hitting a rev limiter in reverse around 1250 rpm.
Any ideas?