I tow a 26' Bonair fifth with it and the truck loaded with way too much stuff. I averaged 18 mpg (imperial) and briefly hit 20mpg when the wind co-operated. Edmonton to west central Min. This is down slightly from previous years but I have turned up the fuel a bit too much and the ultra lo sulfur fuel is a factor. I suspect that this is roughly equivalent to 16mpg with the puny lil 'merican gallons. Speeds are around 60 mph. Most of the way is fairly flat but there are nasty winds at times. Rural mpg with no trailer are around 27 to 28 Miles per Imperial Gallon. Mpg seems to drop when it gets hot, say 90ish. I think this may be due to the lack of intercooling. Temps are not bad though. I usually have to take my foot out of it near the top of longish grades to keep below 1100 degrees (post) but find that taking a bit of an acceleration run before the climb lets the air stay ahead of the fuel and she stays fairly cool. My worst unloaded mpg is in the city where it drops to the low 20's sometimes. Not too bad for a three quarter ton tuck with almost half a million Kliks on the ODO.

 

I get 11 mpg towing my 5th wheel 9500 lbs. Without trailer around 19 mpg.

 

Head wind and mountains 13.5 to 13.9 normal pulling between 15 to 16 Can mpg thats pulling a 25 ft TT thats all on paper, the overhead is wack since put in the ZXT tow chip. but then I get 22 to 25.5 mpg at 65 empty, this 06 gets way better mileage than my old GMC diesel.

 

32ft, 10500lbs, 12'4" high fiver. 15000 miles on my truck. I just went to grand tetons from Helena. 12.7 going and 14.8 coming home. This included about 80miles non towing, drove to jackson from coulter bay and filled up in jackson. I was towing at 65 outside the park and around 50 in the park. 19 unloaded driving 68.

 

10K miles on the '99 CTD with 25ft Airstream on behind, mixed terrain (AL, TN, AR, NC) at about 65mph... 15 mpg. Hope for somewhat better economy with the 2005.

 

well i must just drive fast or something because i just did a trip to south florida 600 mile round trip and averaged 11mpg at 75-80 with a 25' GN with the mud truck and 2 4-wheelers rolled on the scales at 19,650 gvw

 

Just returned from a 1500 mi. round trip. Denver to Sedona AZ. through the mountains and four corners. over all avg. aprox. 12.5 to 13 MPG. Pulled a 5800# TT. Several Passes and winding roads.

 

11-12 pulling my 10k TT.

 

We Went to Little Sarah in OK. My GF was driving her new Dura Max 1 ton, she was hauling the ATV's (6 ATV's on the tailer) and i was hauling our 5th wheel 28.5 ft Jayco around 11k and My truck got 14mpg and she only got 10mpg. We both where doing around 70-75 mph.
She was not a happy camper.

 

19,000-22,000 pounds avg 300 miles to 35 gallon tank!!!!! Overhead says anywhere from 8-9.4 depending on speed!!!!!!!

 

Just curious, what does a map sensor have to do with it.

 

I drive on mostly flat land here in Texas. My most of the time tow is a dual axle 235/75-15 tire 350 gallon tank trailer that weighs 5,400ish full and 2,000ish empty. I get high 17/low 18 towing it both ways.

I had 13 pressure washers stuffed on to a lowboy rather ratty trailer from North Texas back to Shepherd and I got high 16 for that trip.

And in my sig is the average of all driving and all towing for a little over 100K miles.

 

230 mile trip down from the finger lakes region of NY back home to the Hudson Valley pulling a 48' goosneck enclosed race trailer (about 14k lbs). 55 mph most of th way yielded 15.3 mpg hand calculated

 

Im getting about 13mpg with my 37' 5th wheel. (15,000#'s about)

 

Pulling the 32' horse trailer w/living quarters (8880 lbs empty) and loaded with all the gear and horses probably around 12K, i'll get about 12 doing 70 on the interstate thru the Flinthills, if i slow to 60, it goes to about 14....