Suspicious Trip Readings?

[DIG]

I took a road trip to Lake of the Ozarks Missouri this past week from Colorado and back. . I was towing my 35’ 8,000 lb. travel trailer. I mostly ran about 73 mph (tires only rated for 75). Some roads 65 mph. Maybe 100 of the miles were not pulling the camper. It was a little windy in places but not too bad. I normally pull in the mountains and get around 12 mpg when doing so. Anyone have anything to say about the MPG’s I got on the trip? Seemed a little low to me. I figure I’m getting 12 mpg anytime I hit the tow/haul button. The one odd thing that happened was 1400 miles after filling up my DEF for the trip it gave the add DEF warning in 500 miles. Normally go a lot longer than that even when pulling the trailer. Then after I got home and got my mail the paper copy of the TCM and PCM recall was in there and now I’m thinking it’s all tied together somehow!

 

[Fuzzy]

Usually that mileage is not for the whole trip.....it's just the last 30 min of your trip due to the mpg readout the truck uses in the mpg readout....

I used to set my trip 2 to oil change interval to ck mileage...I track every tank in the fuelly app...and it does not usually match when towing....hand Calculated is the on,y real way to get real mileage numbers...

 

[StrokinOut]

There is another screen that shows an average every 30 minutes or so. The one on the display is an average since last reset, which appears to be 1643 miles. The average in the truck is often not the same as hand calculated, mine always reads close to 1 mpg higher than when I hand calculate. If yours is close to being right I wouldn't think that MPG to be too low, 1.2 MPG less than you are used to seeing.
I don't tow an RV so can't really compare, but I get as low as 13-14 average when in town, completely empty. Even on the highway anything over 70 mph I start to lose MPG. I can imagine tugging a big trailer at those speeds would not net great results.

The numbers in this thread seem to be consistent with what you are seeing. https://www.fordtremor.com/threads/towing-mpg-seems-low.4713/

 

[Mike2095]

I’ve got a 22 F350 Tremor with a 6.7, I just towed a 12k lb 5th wheel from Central VA to Central KY and back. I saw very similar mileage as yours. I had the same thing going on with the DEF mileage remaining. I’m now convinced once it goes into tow haul mode, it consumes way More DEF for some reason.

I’ve not received anything on any changes from Ford. I’m curious on if that will change thing’s particularly with DEF consumption. Filling it twice (start and mid trip) in a 1500 mile trip is ridiculous