On our recent trip from Iowa to Lake Powell I checked the mileage on 3 vehicles traveling together pulling nearly identical 22 cruisers over the same route at the same speeds (65-70 mph) The results were very close.
My Chevy Extended cab, 1/2 ton, 4 wheel drive, V8 5.3 engine 11.4mpg
Ford Explorer, 4 wheel drive, V6 trailer tow package 10.9mpg
Ford 3/4 ton, Extended cab 2 wheel drive, V8 6.0 engine 10.3mpg
Don't know what mileage the other 2 get without the boat but
my Chevy 5.3 4x4 usually gets around 18 highway mpg without the boat and less than 10mpg pulling my bigger offshore fishing boat.
The V6 Ford Explorer was able to keep up with the V8's at highway speeds even in the mountains.
My Chevy Extended cab, 1/2 ton, 4 wheel drive, V8 5.3 engine 11.4mpg
Ford Explorer, 4 wheel drive, V6 trailer tow package 10.9mpg
Ford 3/4 ton, Extended cab 2 wheel drive, V8 6.0 engine 10.3mpg
Don't know what mileage the other 2 get without the boat but
my Chevy 5.3 4x4 usually gets around 18 highway mpg without the boat and less than 10mpg pulling my bigger offshore fishing boat.
The V6 Ford Explorer was able to keep up with the V8's at highway speeds even in the mountains.