BigMcLargeHuge

Yours is just a newborn. For the first 10,000 miles or so, I never cracked 17mpg on a highway trip. Now I average almost 20mpg per tank.

Tatunka

Mine is the opposite, I used to get 17-19 MPG on the highway until about 12,000 miles. Now the best I can muster is 15-16 highway. So my average was at 15.8 now 12.5.

Mojoron

I'm still sucking on Mpg after 22,000. Today went 545 miles from Pine Bluff, AR to Manhattan, KS into a NW wind of about 15 to 25. I was barely pushing 12 mpg @65 mph. 2011 4x4, 3.73 Platinum SC with a ARE topper. I have tried to get rid of this pos, but would loose too much money on a trade. I've had the computer re-flashed twice with no effect on mpg. I routinely use a SuperGauge when driving and adjust my driving habits accordingly. If I try to go over 75 into the wind I loose 3 to 4 mpg. In 2011 they only put a 27 gallon tank on the car making my cruising range 275 to 300 mptank. I hate this truck.

JerryC

There's definitely something wrong, our 96 Bronco 4wd/351 with 31x10.5's got 12 mpg on our trips to Dallas at 65-70mph.

Are the front hubs stuck locked on?

The wifes FX2 made the trip from the Dallas TX to Memphis TN on a tank of gas with plenty to spare, we put another 40 miles on it before we filled it up. Usually have a decent tailwind on that trip but it's still pretty good mpg.

TwinTurboFx4

A head wind will kill mpg. I just got back from a 2600 mile road trip and averaged 16.5mpg. But I was heavily loaded in my truck and alot
Of city traffic. From Michigan to kcmo today I had a 15mph head wind and I was doing 75mpg ish and only got 15mpg.

Buz

My computer almost always reads .5 mpg low!

Guess there are discrepancies among these computers...

Real world numbers after filling an empty tank should be the only mpg numbers allowed on these threads.

Buck50HD

2012 XLT screw 157" HD payload 4x4

Highway with 87 E10 at 63mph: 21

Mixed driving (<65mph hwy, some gravel, some small town): 17-19

Best: 24.5 for 70 miles with prem non-ethanol <60mph

Towing 7500lb 26ft tt with 87 E10: 8.7-9.5

Best towing same trailer: 10.5 with prem non-eth and slight with wind

I saw best mileage new and has been getting slightly lower but still very good. Might need to try premium non-eth again.

Display reads right on to slightly optimistic by about 3% so really close.

BigMcLargeHuge

Could be other mechanical problem. Could it be stuck in Tow Mode even without selecting it?

onyx

Best yet to date. The fuel used was off by a gallon though. So instead of 17.4 which the truck said, it was actually 18.3

Also, after calculating my mpg i got 24.9, where the truck says 26.1

My lifetime avg is 22.0 according to the truck AND hand calculations.

Vader

If you want your milage to stay peaked on these EB's, keep the HPDI's clean with high detergent fuel. Use teir 1 gas, and use a good injector cleaner every oil change. HPDI engines are picky about being clean.

I just installed the Livernois tuner, and will watch to see how that affects mileage. I have been averaging 19-21 on the freeway. In town, I get 16-17 so far without the tuner. 4x4 with 3.73 5500 miles