I for one think it is much more important to see what the road sees as your hooked and ready to go! for instance, my setup looks like a 6700lb truck towing 14000lbs of trailer if its unhooked....but once I hook her all together the axles and road see a 10000lb truck towing a 11,700 lb trailer. But it is nice to know what your base numbers are so getting all the weights is handy.
2007 Cardinal 362bhle 5er
2006 f350 Diesel CC LB 4x4 4.10 locker lariat
1966 Mustang coupe...under construction
2004 Explorer 4.6 awd (16 year old daughters car)
2009 Mazda 6 (wife's ride)