Sure he can tow 'just about anything' but to stay below 9,000 GVWR that the factory says is safe, then he should take the truck to a scale with a full tank of fuel. Then he will know that the base weight is really 7,000 or 7,400 pounds with 4 wheel drive. Or whatever the actual weight is.
Then find a travel trailer with a 1,000 pound hitch weight and stay below the 9,000 pound capacity. Taking the truck to 10,500 pounds 'Just because it does not sag much' is not really safe or recommended! Just because he did not exceed the rear axle rating (7,500 pounds in most 3/4 ton trucks and even the dually's) or tire ratings (3,042 per tire in 16" rims and a lot more with 17 or 18" E rated rims) does not make the 9,000 GVWR go up a pound. Being a little overweight might not get you in trouble, but a crash, the lawyers get involved, and your insurance company can dis-own you if they find out that your truck weight was well into the 10,000 pound range while only rated at 9,000 pounds.
Good luck!
Fred.
Money can't buy happiness but somehow it's more comfortable to cry in a
Porsche or Country Coach!
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