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6.0L Fuel Economy

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358K views 357 replies 180 participants last post by  shakenfake  
#1 ·
Calling all 6.0 owners- what's the average fuel economy you're getting? Regardless of mods, I'd like to hear your stories...

I'm getting about 11.5 on winter gas, with about 75% of the tank spent on city driving.
 
#2 ·
I was getting about 14 mpg with an 170k+ engine that was really gunked up. I now a 40K engine, but have not figured gas mileage up as my cluster is bad, and other issues. I mainly drive city (small town), when I get to go somewhere and drive the average varied between 15 and 16 at 60 mph average speed.
 
#4 ·
I noticed where I get my gas from greatly affects my gas mileage. When my wife gets gas at our local Marathon she gets about 28 to 29 mpg in her 04 Impala SS, anywhere else is around 22mpg avg. If I get gas there I am lucky to get 10 or 11 mpg. I think the gas station I get gas is BP, but not sure!
 
#5 ·
The way people figure this varies greatly so it is hard to compare. Some will take how much fuel they put in their tank when fueling up and take the mileage they got and figure out the MPG from that. Others will wait for the best road setup and use the driver information screen to have it calculate for them. If I get on a flat enough road and hit cruise at 65mph I can get over 20MPG with my 6.2 but any slight hill or if I have to pass and it will go down.

So how does everyone measure MPG so its easier to be more accurate when trying to compare. ????
 
#6 ·
Measuring MPG:
1) Fill tank.
2) Reset odometer
3) Drive truck until tank is almost empty.
4) Go back to the same station (and if you want to be really accurate over time or multiple tanks, use the same pump) and fill the tank.
5) Divide total miles driven by the number of gallons of gas used. That = MPG.

We've discussed before that the DIC only gives general info, and is somewhat variable. Use it to measure trends, but don't rely on it for an absolute number.
 
#7 ·
That's about how I do it, EKinMN. I'm just wondering if the 11-12 mpg I'm seeing is average. Love the power, love the noise, love the truck, but it's an expensive addiction, ya know.
 
#8 ·
EKinMN said:
Measuring MPG:
1) Fill tank.
2) Reset odometer
3) Drive truck until tank is almost empty.
4) Go back to the same station (and if you want to be really accurate over time or multiple tanks, use the same pump) and fill the tank.
5) Divide total miles driven by the number of gallons of gas used. That = MPG.

We've discussed before that the DIC only gives general info, and is somewhat variable. Use it to measure trends, but don't rely on it for an absolute number.
Haven't done this method with my truck yet will have to try when I get home. I am always having fun on city streets so I would imagine I will have low numbers doing this. When I get on the HWY I take it nice and easy and stay on cruise control.

Well that is till I see a F-150 that thinks he is hot shit or a little import trying to act tough :lol:
 
#13 ·
Hey wannahdawg, welcome to the site! My record for fuel economy is 13.0 mpg. I'm hoping I can get more in the summer, and once I do some more work on the engine (throttle body spacer, custom tune, etc.).
 
#14 ·
I would really like to see some dyno results from a throttle body spacer. Nothing I know about engines (and I know a fair bit) would lead me to believe they'd do anything positive.
 
#15 ·
My plan is to put the TBS on in a month or so, and then save up $500 for the custom tune- it includes a before\after dyno session, plus the custom tune. So, hopefully, I'll be able to see what happens when you add a TBS, CAI, and performance muffler to a stock 03 6.0L. Unfortunately, I won't be able to tell which mod added the most HP. Maybe the techs at the shop could tell me...
 
#16 ·
Does your throttle body have the injectors in it, or are the injectors on the intake runners?
 
#17 ·
My '04 classic crew cab got 14.6 mpg average over 6 month's I used the fill tank track mileage method so this should be as accurate as it gets truck setup was pretty muck stock accept 20" rims
If you have apple phone there is a great app for tracing mileage on auto's it is called gas cubby I recommend it if you are into tracking mpg for your vehicles
still on my first tank of gas on my diesel but so far it looks like 18mpg
 
#18 ·
i'm probably goin to go the better intake route myself, along with a more open exhaust. mines only a reg cab, so i think mine would get slightly better mpg than a crew with 4x4.... just thinking of the wieght differences. i've heard a lot about droning on the exhaust too, so i'm kinda wondering about that. i've got a flow 40 series already from a previous truck so i don't know what i'm gonna do.... but right now some where in the mid 13's is what i usually get, i do about 50/50 mix of city/hwy too...
 
#19 ·
I envy ya'll boyz that get mid-high teens in economy, but it just boils down to me driving a big, heavy truck with big, thirsty engine- with most of my miles coming from city driving.

Hartski- I have no idea where my injectors are. The TBS might not even fit in my truck, because of clearance issues with the fan and the elbow of the CAI. We'll see...
 
#20 ·
EKinMN said:
Measuring MPG:
1) Fill tank.
2) Reset odometer
3) Drive truck until tank is almost empty.
4) Go back to the same station (and if you want to be really accurate over time or multiple tanks, use the same pump) and fill the tank.
5) Divide total miles driven by the number of gallons of gas used. That = MPG.

We've discussed before that the DIC only gives general info, and is somewhat variable. Use it to measure trends, but don't rely on it for an absolute number.
I did this just yesterday. Took a road trip that burned almost a full tank, all 4 lane interstate, pretty flat (Illinois), about 10% was city. When I returned, I filled up at the same BP, and got just over 15.5 mpg. My truck is a 2010 5.3, 4WD, extended cab. I was really hoping for 17, but... oh well.
 
#22 ·
I'm getting about 10-12 MPG or about 260-280 miles out of about 24-25 gallons. I just bought my truck in December so I don't know if it will get better once it warms up outside but I'm hoping that it will (my old 5.8L Ford that I had before got better milage in the summer). I have a 2002 1500HD that does not have the new 6 speed trans that the new body style 07+ trucks have so I'm not sure if that would affect anything. Probably about 80% of my driving is on the highway at about 70mph.
 
#23 ·
I hate to revive this again, but I was wondering why the 6.2s seem to have better mpg numbers than us? I'm pulling around 12.5 so far, I don't really romp on it or do nascar speeds on the freeway. Wondering if the other 6.0s are getting better numbers due to the 6 speed transmissions...