Friday I drove about 275 miles to pick up a travel trailer. Trailer is 31ft bumper pull with a fairly high profile. On the way there my stock 2007 CC 4x4 Classic got 18.0 driving 70-80 MPH. Trailer weighs about 7200 lbs. I was surprised to see that on the trip back, running about 65-70MPH I got 8.6!

I was expecting better. I regularly pull a car trailer that can exceed that weight with a vehicle on it, and I get 13-15 while towing that. I borrowed this trailer from my son, who has a 2004 Powerstroke truck. He told me he gets 13-14 when towing the trailer.

WTF? Is this normal? FYI, I am at 41K, no problems, perfect shape, well maintained with recent fluids and filters.

Mike

weight isnt neccasarily the problem... aerodynamics play a very large role in MPG....

Did you have a head wind?
how are you calculating your MPG... by hand or off the DIC?
How is your son calculating his MGP? by hand, guessing, off trucks computer display? Son driving the same route, speeds as you? was this winter or summer time MPG he quoted?
I know you said you are stock, but do you still have the stock tire size on? larger tires will lower your MPG.

You must have been buckin into a head wind, drove with the wind on the way there and into the wind on the way back. also that travel trailer will catch more wind than a car trailer.

Aerodynamics. Not weight.

must have been wind. we'll see. it is calm today and i am driving from NE Texas to Galveston, again about 275 miles. going to try to set the cruise on about 63-65 and see what i get.

Just like towing a parachute!!!

7.3l do good on fuel and have a bit less power then your Dmax

if the trailer has a high profile you might as well be pulling a billboard behind your truck.

You want to get good fuel mileage towing a trailer then slow down. 62 to 63 MPH should get you about 12. If it is windy it will drop but 8.6 is pretty bad. No comparison between the 7.3 and the DMAX.

wht u expect? just think how shitty big rig diesel get for mpg. when u tow u are more than likely not going to get good milage its just a fact

weight isnt neccasarily the problem... aerodynamics play a very large role in MPG....

Did you have a head wind?
how are you calculating your MPG... by hand or off the DIC?
How is your son calculating his MGP? by hand, guessing, off trucks computer display? Son driving the same route, speeds as you? was this winter or summer time MPG he quoted?
I know you said you are stock, but do you still have the stock tire size on? larger tires will lower your MPG.

..........which can be summed up very nicley as ..........

Just like towing a parachute!!!

it is aerodynamics...weight means absolute Dick all to these trucks.!

cheers,
stk

Friday I drove about 275 miles to pick up a travel trailer. Trailer is 31ft bumper pull with a fairly high profile. On the way there my stock 2007 CC 4x4 Classic got 18.0 driving 70-80 MPH. Trailer weighs about 7200 lbs. I was surprised to see that on the trip back, running about 65-70MPH I got 8.6!

Mike

I agree with the headwind comment, but try pulling a 5th wheel compared to a travel trailer. Now, I get around 12 or so (5th wheel), but I also slow down when towing, too. And if I have a headwind, I may slow down even more.

Remember a travel trailer is an aerodynamic disaster with A/Cs, antennas, domes, vents, corrugated aluminum siding/front (If you don't have laminated sides), awning poles, awnings. Not to mention an underside that has sewer lines, axles, etc.

8.5 is bad, granted, it has to be wind, or speed.

Just thought of something else, did you check the brakes on the trailer, if the trailer is new, they could be dragging...