The payload on the gas version seems decent.
I have a 2012 SL 4x4 and my payload is 1477 lbs.
If this info is true then the XD will be approximately a 600lb increase.
My buddy just bought a 2016 Tundra that is equivalent to the SV and it has 1200lbs payload for comparison.
From the quoted site above:
Model:
S 4x2 = 2,589
S 4x4= 2,519
SV 4x2 = 2,423
SV 4x4 = 2,302
SL 4x2= 2,177
SL 4x4= 2,031
PR 4x2 = 2,106
PR 4x4 = 1,873
PRO4 = 2,247