To give you a point of reference......
My truck is an older 2003 Ford F350 Super Duty with V10 gas. Below are my truck's specs. I tow a 28' Tahoe that's about 8000# dry and about 10,000# loaded. It does have a GVWR of 13000# but I will never get to that weight as I will never carry more than 2000# of stuff. TW is 1500# with full water tanks (100ga). I also do not carry off road toys.....just bicycles, raft, outboard engine, fishing gear, ice chests, camping gear, etc. I am within specs for towing safely.
Payload: 2980#
Front GAWR: 4250#
Rear GAWR: 6830#
GCVWR: 20,000#