So I will start off by saying that it's a 1999 2500, it is wicked doggy on take off with alot of black smoke witch is unusual for this truck until the turbo spools up, so basically at 55 mph with 3.54 gears it's turning ~2100 rpms and refused to up shift, manually shifting doesn't work either

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Sounds like limp mode of the transmission.
Do check the fault codes and let's go from there,

 

Well that's where I run into issues, there's no light and the obd2 connection has no power when I pulled a code out with the key it was p0749 I believe

 

P0753 is what it is it is still in the system

 

That's the shift solenoid code.................. Could still be a couple of things, but I would start by checking out the solenoid.

Some reading to get you started.

https://www.dieseltruckresource.com/...v-auto-222006/

Code P0753 repaired (long) - Dodge Cummins Diesel Forum

 

Hey all well as it turns out, when I had my fuel issue I switched a bad relay to the transmission relay spot, and hadn't driven it since I got it to fire so I threw a new relay in its place and shifts through the gears like a million bucks now

 

Great!

 

Who would have thought... no power to the transmission results in weird behaviour.

Glad that you found it, and that it was a cheap fix.