Changing the hitch receiver will not alter your truck max weight rating (GVWR) or max tongue load, unfortunately. Both are truck structure (frame) related. Max tow is based on what the engine, transmission, rear end gear ratio can PULL, irrespective of the load on the frame. All tongue/pin load is TRUCK CARGO and reduces the amount of stuff/people that can go inside the truck as well.
If you feel uncomfortable with your combination, a truck model upgrade may be in your future.
Lou and Laura with Bella - German Short Hair Pointer
2008 GMC Sierra 2500HD Crewcab SB Allison Duramax
2010 Flagstaff 8526RLWS - Superglide 3300
HAM CALLSIGN - KC3FFW