[supton]

Seems low, but am not sure it's that low. How fast do you drive? What tires are you running, and at what psi? What else do you have in the truck besides yourself? Did you install a cap on the bed? How many miles on the truck?

How do you know the ECU registered the fuel as E85? I wonder if there is a sensor off--I'm guessing it "knows" E85 usage going by reading the O2 sensors and realizing the air/fuel maps is off, not by any particular ethanol sensor. It could be a bad O2 sensor.

 

[supton]

Sorry to hear about your woes. I suspect the dealer will do nothing, as the mpg is within the EPA estimates. I would track mpg the old fashioned way, paper and pencil, just to verify the computer though. If nothing else it may help with the lemon law bit, if you have data showing low mpg.

 

[supton]

its so sad i have the same issues i have a 2013 rw crew 4x4 and i almost dont even like my truck because it literally gets about 9 mpg...the sticker said 13-17 epa not even close...

I am having an issue with 2 other things on the truck

1. In 2wd with the trac control off the front end is making a clunking loose sound like the thing is gonna fall apart,

2. on the fwy a big sweeping turn the truck sounds like gears are binding at 45 mph through a big sweeper...

i really like my truck but these issues are forcing me to not take her on long trips which i bought the truck for with the crappy gas milage...

Lemon here i come....should i take it o the dealer for the MPG? is this a valid argument i feel like i have been mislead!

I'm not sure why you are driving with traction control off, but it sounds as if 4WD is stuck on. I would complain, as something is amiss, and I think it's in your transfer case / differentials.

When you are in 2HI, and make a tight turn, like steering wheel at full lock, does the truck roll freely; or does it feel like it is binding?

 

[supton]

If it's burning gas but not moving, average mpg will drop. mpg is miles divided by gallons; if it burns some fraction of a gallon but did not move, then the result is a lower number.

I always like watching my SG as I drive off from the station, and it says I'm getting 4mpg. It'll climb up to say 12, then drop to 10 at a stop, etc. It fluctuates less the more miles I gather on the tank. What's sad though is watching the instant mpg while driving up a hill.

 

[supton]

It probably used some sort of rolling average, say mpg over the last hour or the last 10 miles, and perhaps it ignored when sitting--or at least didn't update the display until moving again.

While I have the SG monitoring, I go by the tank avg, as calculated when I fill up.