So here is the math that I did while back for loading my trailer with fully loaded Max25 tractor and pulling with a V8 Dakota but I never towed it with the Dakota, but rather a 3/4 ton Ram. I have a Big Tex Trailer CH60 trailer. Works great for it! My tires are loaded with RimGuard and that is calculated in. I did run it over the scales for grins, and it came out pretty close as I recall.
Turf tires
Fronts: 20x8-10 Gallons 4.0 Weight 42.8
Rears: 29x12.5-15 Gallons 14.0 Weight 149.8
Tractor 1693
Tire Ballast 384
Loader 545
Backhoe 725 (w/o bucket)
60” mower 411
Total 3758
Big Tex 60CH-16 GVWR 6000# Weight 1,670
02 Dakota curb weight=4599+ (3758+1670=5428)10,027 gross (GCWR)
05 Dodge curb weight= 6216+ (3758+1670=5428) 11644 Gross (GCWR)
Hope this helps.
Erik