mpg questions

[hammett88]

for those with spartan tunes..turbo backs and intakes.. what kind of mpgs are you seeing??.. and what tunes give the best mileage??.. how bad do tires hurt.. like 35s and 37s??.sometimes on diesels depending one were the torque comes in.. tire don't hurt too bad.. idk how it effects the 6.4 though.. thanks for you help guys..

[FX4STROKER]

from what I have read you should be around 19-22 mpg on the higway depending on how you drive. Tires dont really matter much if you go with 35's thats only a inch bigger then stock

[hammett88]

19mpg?!!!..i can go with that!!!!..

[08stroker250]

35's are 2 inches taller than stock, but they still don't make that much of a difference. If you stay with stock or 35's, you should see pretty decent mileage on the interstate if you keep it under control. I usually run 70-85 mph on the interstate and get anywhere from 16-21 mpg. I drove from Kennesaw, GA to Hilton Head Island, SC tonight running 75-90 mph. I filled up in Kennesaw, drove 5-6 miles before leaving, left to head to South Carolina, pulled off the interstate about a mile to eat, back on the interstate and drove 316 miles. So that is around 322-323 miles. I have about a 1/4 of tank left. I would say thats pretty good driving 80 mph 85% of the ride.

[drservo]

Mine gets 18 hwy, 12 city 20" factory wheels and tires

[DavidPhillips]

Honestly, there have been many threads like this. Tuner or not there is such a wide variance that it's not worth considering until you get yours and see what it does.


I can tell you that it was not a consideration when I got my truck but I am surprised at the empty mileage I get. As far as towing I believe it is competitive with any new model out there. If I was towing all the time I think it could be improved by changing tire size. It would likely lower my empty mpg.

10.5 average long haul towing and 19.5 overall average empty. 65 to 70 average mph.

[08stroker250]

Originally Posted by DavidPhillips

Honestly, there have been many threads like this. Tuner or not there is such a wide variance that it's not worth considering until you get yours and see what it does.


I can tell you that it was not a consideration when I got my truck but I am surprised at the empty mileage I get. As far as towing I believe it is competitive with any new model out there. If I was towing all the time I think it could be improved by changing tire size. It would likely lower my empty mpg.

10.5 average long haul towing and 19.5 overall average empty. 65 to 70 average mph.

Will you clarify if you have a tuner or not David....

[2008TTCC]

I can say that with ULSD my truck running 37 at ~70mph my truck wont do better than 14-15 mpg with cruise control on....

[hammett88]

Originally Posted by 2008TTCC

I can say that with ULSD my truck running 37 at ~70mph my truck wont do better than 14-15 mpg with cruise control on....

what mods do you have?..

[08stroker250]

Originally Posted by hammett88

what mods do you have?..

He has a Spartan tuner, but he is also lifted and has 37" tires