Originally Posted by canadiankid
snip..... Really the best case scenario.
I would agree.
I believe your new 2015 2500HD has an OEM receiver with a 2 1/2" pin box, which may/or may not effect the size of your new draw bar purchase preference (2" or 2 1/2"). I'm guessing that your prior 2009 1500 OEM receiver came with a 2" pin box.
The 2 1/2" receiver comes with a steel adapter sleeve that will accept a 2" draw bar. If you elect to stay with a 2" draw bar I would confirm the "Weight Distribution Mode limit" if using the adapter sleeve, and that it still meets your TT's "loaded" tongue weight. The adapter sleeve may have a weight specification sticker on it (or refer to owners manual).
What I don't know is if the 2 1/2" to 2" adapter sleeve has the same tongue weight limits as a OEM receiver with a 2" pin box.
Just food for thought...