Just took a trip from Knoxville, Tn to Texas in my '06 Scab 5.4, 3.55 ls ...
brought back my new Skeeter bass boat....1200 miles, averaged 14.5 mpg @ 70 mph..luckily I20 is mostly flat and I had it in o/d....just wondering what you guys that tow boats are getting...I was pretty satisfied with the mpg and the performance of the truck....just curious...

 

I don't tow a boat, occasionaly one trailered jet-ski and that for only about 30 miles round-trip, but I'd say 14.5 mpg is great mileage hauling a Skeeter!

 

i tow a 21 foot essex boat....it weighs about 4800 lbs with the trailer and semi loaded. i get about 10mpg towing through the desert about 240 miles each way. there's a lot of hills so im constantly dropping into 2nd....rarely in OD. the truck performs ok...not great, but i have 33s and 4x4 crew cab long bed so its a lot of weight to move to begin with.

 

Towed my 1989 19' Dynatrak to the lake yesterday. About 50 miles one way. O/D off at 60 mph. After idleing on the ramp and everything I averaged 11 mpg.