I relocated from the SF Bay Area to a small town outside of St. Louis. Made the drive last week. I think my mpg's are funny enough to post...

Left with a full tank from Menlo Park on 12-29. Arrived here on 12-31. 31 hours total driving time, and the Garmin told me that my moving average was 72mph. I had the cruise control on for 90% of the trip at 5mph over the max posted limit.

Tank 1: 30.0 gallons, 409.6 miles, 13.6 mpg
Tank 2: 26.4 gallons, 331.6 miles, 12.6 mpg
Tank 3: 31.0 gallons, 438.1 miles, 14.1 mpg
Tank 4: 31.2 gallons, 423.1 miles, 13.5 mpg
Tank 5: 28.9 gallons, 352.7 miles, 12.2 mpg
Tank 6: Haven't burned all of it yet, only local driving anyway...

So, at a speed of 72mph, my overall average for the trip is 13.2mpg (overall mileage average for the life of the truck is 12.9). I ran the TNT program with default settings on level 3. I was too tired to deal with swapping programs to test for differences in mileage.

I have a few things to say:

1. I miss my '03 dearly. It got a solid 4mpg better with the same lift/tires.

2. The 6.7 doesn't look so bad to me any more. Can't be any worse than my truck. I think my truck has an identity crisis.

3. I'm glad diesel is $1.999 here in town!!! (though I'm sure it won't last)

 

And I'll add that when my tires are toast, my truck's going back to stock height with some Toyo 285/75 AT's...

 

Is that empty? You should have changed the Smarty program. I made a similar trip in Sept and played with the Smarty. The revo with the highest timing setting set on SW3 got me the best mileage at 19.6mpg. You had too much fuel and not enough timing.

 

I agree, the tnt tune has given me the worst highway mileage yet. The best has been with 4.4 The pod has helped a little in town but has done nothing for the highway

 

Sure sounds like you got a lousy mpg truck.

I make 400 mile round trips to Austin back a lot. Just driver there stop and drive back without even turning the truck off. I usually average about the same moving average 72-74mph. With my current mods in signature, Smarty PoD TNT-R SW #9 PoD=45, EZ on Level 1, TST off, I averaged 17.9mpg with cruise set on 74mph yesterday. That is a little lower than before the lastest mods and Smarty regular TNT, it was usually 18.1-18.5 depending on the wind.

 

Which tm, tq and rp did you run when you get the best mpg?

 

sw3, torque 4, rail pressure stock, timing 4, wastegate off

 

I thought higher tq settings kills the mpg?

 

Me, my dirtbike and 200lbs of gear. About 800-900lbs total...

I'll do some testing before the return trip in June/July! I'm loading up the Revo software on the Smarty now!

Best mileage I ever got was one tank at 16.1 with the truck bone stock and less than 5000 miles. Weird. I've got 22k now, lifted since 5k miles. Smarty and the trans work did nothing to improve my mileage.

 

I haven't decided yet. If you can be really easy on the skinny pedal, you barely have to touch it to get the truck moving. If you're not really easy on it, then a higher TQ setting would most definitely hurt mileage.

 

I'm sure the lift hurts mileage some. You can get close to 20mpg with 35s/315s, but not sure if that's true with a MT like you have. Mine are ATs.

 

That's about what I get with tnt/r. I would always get high 19's or low 20's with the beta 4.4 and the only thing that has changed is the turbo

 

My '03 305/555 would get 18-19 regularly with the same tires. I think for whatever reason I have one of the fuel guzzlers. Luck of the draw, I guess...

At least my truck is still faster than a gasser, even if it gets the same mileage.

 

Where did you move to, I am just west of STL...

 

My 05 with 6 inch lift on 37's gets 18.4