towing with suv???

Both our answers are correct since the Gross Combined Weight Rating GCWR of the Acadia is 10,450 lbs and the actual weight of my AWD Acadia is 5062 lbs, the remaining allowance for extra weight is 5388 lbs. Once you fill up the gas tank and add the 150 lbs for the driver that is allowed without calculations (as per owners manual the payload accounts for that 150 lbs already)you have approximately 5200 lbs available to split between trailer weight and cargo / passengers.

Just to show my calculations:
My Acadia does indeed list the GVWR as 6459lbs as you stated, and lists maximum payload as 1397 lbs.

GVWR of 6459 lbs minus 1397 lbs payload equals 5062 lbs total weight of the Acadia with all options and battery installed.

Take the GCWR of 10,450 lbs and minus the GVWR of 6459 lbs leaves a total of 3991 lbs of towing capacity if my Acadia is fully loaded.

Take the GCWR of 10,450 lbs and minus the Acadia weight of 5062 lbs leaves a total of 5388 lbs of towing capcity if my Acadia is completely empty and without ant fuel LOL

So as I've already mentioned, any weight you put into the Acadia will decrease the maximum towing rating. It is that low GCWR of 10,450 lbs that really limits the Acadias ability to tow a travel trailer.

I see where you're coming from now. The way it was worded made it sound like you thought the GVWR was 5200lbs and that was all the Acadia could weigh.