Mine is a F350 6.4L CC long bed 4X4 with 3.55 gears.
Guys who claim 20+ MPG out of a 6.4.....
- Thread starter SID297
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Mine is a F350 6.4L CC long bed 4X4 with 3.55 gears.
What size tires do you have and what speeds do you drive. I've never gotten close to that kind of mileage, but I have factory 20s and 3.73s.
When I got 22 mpg on my trip to FL. I had 285-60-18's I believe and they were Goodyear Duratrac tires and I was going 65-70 mph. Now I got 20" wheels with 325-65-20 Duratrac tires and my mpg has gone down quite a bit. I know avg about 18.5 mpg per fill up. Which still isn't bad for a 9200 pound truck and 36 inch tires.
I'm running 285-70-20s and run about 70-75 usually. I haven't seen anything much better than 17MPG.
Just checked my mileage while towing 9,000 lbs, came out to right at 11 MPG.
I don't know man. Maybe it's the tunes you are running.
my truck gets driven back and forth to work on a 60 mile round trip M-F. When stock the best I ever got was 16.1MPG hand calculated. My lie-o-meter on the dash said I was actually getting 17.5. This is a 60MPH there and back without cruise control. I notice with cruise control on it hovers around 11lbs of boost at all times and when I just drive it I am typically around 8lbs of boost.
Now I have modded it since. It has full MBRP turbo back exhaust with delete. MiniMax tuner running a KEM 345 tune. Hand calculated at the same 60mph I get between 19.4 - 19.8. So I did not get a ton of MPG with those mods.
The truck is a 2008 F-350 Super Crew FX4 Long bed. The power difference from stock to the KEM 345 tune is insane. I beat my buddies '07 GT that is basically stock from a roll and a dig.
Now I have modded it since. It has full MBRP turbo back exhaust with delete. MiniMax tuner running a KEM 345 tune. Hand calculated at the same 60mph I get between 19.4 - 19.8. So I did not get a ton of MPG with those mods.
The truck is a 2008 F-350 Super Crew FX4 Long bed. The power difference from stock to the KEM 345 tune is insane. I beat my buddies '07 GT that is basically stock from a roll and a dig.
Just averaged 19.6 during a trip from Augusta, GA to Cincinnati, OH.
F350 CC longbed 4x4. H&S tuner, S&B intake, King Offroad leveling kit, stock 20" wheels and tires.
Power setting on mild
F350 CC longbed 4x4. H&S tuner, S&B intake, King Offroad leveling kit, stock 20" wheels and tires.
Power setting on mild
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Hand calculated? What gears?
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Don't go by what the lie-o-meter says.
over 600 miles on a tank so it is not too far off
my 2010 F250 with 373 gears, spartan tuner set to 300LL, 4" down pipe, 5" exhaust, AFE intake, averages 15 to 16 mpg in the city. I took a trip from Anderson SC to Daytona FL and averaged 19.6 running 75mph. The best I ever got before all the mods was 14.1 on a trip to Charleston SC. I know Im not getting as good as the old 7.3 and 6.0 but compaired to stock I really cant complain! and the power of this truck has made me question why I am keeping the Lightning..... but at this point the L is like a family member. haha. These numbers are all hand calc. My lie-O-meter says Im getting between 21 and 26 mpg.
Are you sure it has 3.73s? I thought 2009 was the last year for them in SRW trucks.
You are correct. had 3.73 in my head from reading all the posts. I have 3.55's. You could still get 3.73 in SRW but it had to be ordered that way.
I get my best mileage driving on the hottest tune, as long as I keep my foot out of it.
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