Diesel mpg help
Lead Driver
Joined: Nov 2011
Posts: 9,544
Likes: 43
My speedo is obviously permanently set to km, as it's a Canadian truck....
But you can switch the screen to either or....
Do you even own a 6.7??
Postmaster
Joined: Sep 2006
Posts: 2,598
Likes: 5
From: Maryland
I have a 2011 F-250 6.7 3.55 Ratio. I pull a 36' RV a lot of the time. When not pulling the RV on a good day in the best driving conditions I can average 13.4 to 14.2 no mater what! When pulling the RV I only pull it in Tow Haul on Hwy I drive 60 MPH. The RV weighs loaded 12,300 Lbs. I averaged over a 6000 mile trip 5.8 MPG.I love the truck but wouldn't consider this type of mileage anywhere close to good, with or without a load.
Has your truck ever been reflashed at the dealer? I have heard a lot of complaints of lower fuel economy after a reflash here lately. Some even complain of reduced power.
Tuned
Joined: Dec 2011
Posts: 302
Likes: 5
Yes, i do have a 6.7l. This is my second 6.7l. My first 6.7l was a 2012 F250 xlt SC LB. My current truck is a 2013 F350 lariat 6.7l 'CC LB.
My first PSD was a 1997 7.3l. Second PSD was a 2001 7.3l.
Lead Driver
Joined: Nov 2011
Posts: 9,544
Likes: 43
I am aware of that, but your mte is miles not km. So the math based on your last fill up iis 18ish.
Yes, i do have a 6.7l. This is my second 6.7l. My first 6.7l was a 2012 F250 xlt SC LB. My current truck is a 2013 F350 lariat 6.7l 'CC LB.
My first PSD was a 1997 7.3l. Second PSD was a 2001 7.3l.
Yes, i do have a 6.7l. This is my second 6.7l. My first 6.7l was a 2012 F250 xlt SC LB. My current truck is a 2013 F350 lariat 6.7l 'CC LB.
My first PSD was a 1997 7.3l. Second PSD was a 2001 7.3l.
For a 38 year diesel mechanic, I think you would understand what an emission less diesel could do....
Tuned
Joined: Dec 2011
Posts: 302
Likes: 5
Yes, my truck is switched to miles in that pic. Again....I came off a MAIN highway going 110km, turning on to my highway, to my home town which is 170kms, speed limit is 80km and yes I do that on this road with the nightlife we have here, so I probably was closer to 19/20 on the MAIN highway. I repeat I was playing with the settings on my tuner to get that, on this trip I found performance setting I was getting 1+ mpg, which I have stated before on this forum.
For a 38 year diesel mechanic, I think you would understand what an emission less diesel could do....
For a 38 year diesel mechanic, I think you would understand what an emission less diesel could do....
Even with all the emissions junk these new diesel engines have, the get better fuel economy than the old diesels. If you read my post on the second page of this thread you will see that i stated "cleaning exhaust filter /regen is a efficient way of wasting fuel ". So you are not telling me anything I don't already know. IMHO, think that you are stretching a bit what fuel mileage your actually getting. There are other here that that have posted their actual life time fuel mileages in spread sheet form. Do you dare do the same?
Lead Driver
Joined: Nov 2011
Posts: 9,544
Likes: 43
You should look closer at that pic. You see the tank is pretty much full, so I obviously filled up. As you the master diesel mechanic has ALREADY stated, is based on your last mpg. Now look even closer, because even you mr. Sherlock missed what a few others noticed, my history is that pic. How could I "trick" the truck for that long, do you REALLY think one could coast that long? I feel I'm losing IQ continuing this conversation...
Tuned
Joined: Dec 2011
Posts: 302
Likes: 5
You should look closer at that pic. You see the tank is pretty much full, so I obviously filled up. As you the master diesel mechanic has ALREADY stated, is based on your last mpg. Now look even closer, because even you mr. Sherlock missed what a few others noticed, my history is that pic. How could I "trick" the truck for that long, do you REALLY think one could coast that long? I feel I'm losing IQ continuing this conversation...
Freshman User
Joined: Mar 2013
Posts: 31
Likes: 0
Millage
I hear what you are saying. I wish I could say I need to have the filters changed and I might be running the DEF fluid low, but that isn't The case. I had my filters changed at the Ford dealer when I was first started experiencing the poor MPG. They only way I have any indication of the DEF level is low is by checking the computer for levels, which I do Often. I love my truck and guess I will just live with the poor millage. Wish there was something guaranteed I could do to work, because believe me I would do it, guess I need to buy a fuel station.
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Hotshot
Joined: Nov 2000
Posts: 11,591
Likes: 14
From: Pflugerville, tx
I hear what you are saying. I wish I could say I need to have the filters changed and I might be running the DEF fluid low, but that isn't The case. I had my filters changed at the Ford dealer when I was first started experiencing the poor MPG. They only way I have any indication of the DEF level is low is by checking the computer for levels, which I do Often. I love my truck and guess I will just live with the poor millage. Wish there was something guaranteed I could do to work, because believe me I would do it, guess I need to buy a fuel station.
Freshman User
Joined: Mar 2013
Posts: 31
Likes: 0
MPG
I think you have a problem.
when was the last time your fuel filters were changed?
my 2012 f250 (3.31 gear) was getting 15.2 average over 13000 miles and climbing (as long as I didn't tow). on the highway I could get >18 if I stayed under 75mph. towing my 7,000 flat front enclosed car hauler was 10.8.
my new (to me) 2012 dually (3.73 rear), was getting 9.5 towing my 12,500lb FW at 65-70 (g rated 75mph tires), and 15.8 not towing at 70-75mph.
I did notice lately the MPG seemed lower 14ish, and I replaced the fuel filter. the next week I had to drive to Oklahoma city and back, uhaul up, empty back. got 14.6 up (60-65), and was over 17 back (70-75)
maybe your def tank is having trouble too.. seems a bunhc of 2011 users early on complained of low mileage when the def tank didn't work properly.
when was the last time you filled the DEF tank?
when was the last time your fuel filters were changed?
my 2012 f250 (3.31 gear) was getting 15.2 average over 13000 miles and climbing (as long as I didn't tow). on the highway I could get >18 if I stayed under 75mph. towing my 7,000 flat front enclosed car hauler was 10.8.
my new (to me) 2012 dually (3.73 rear), was getting 9.5 towing my 12,500lb FW at 65-70 (g rated 75mph tires), and 15.8 not towing at 70-75mph.
I did notice lately the MPG seemed lower 14ish, and I replaced the fuel filter. the next week I had to drive to Oklahoma city and back, uhaul up, empty back. got 14.6 up (60-65), and was over 17 back (70-75)
maybe your def tank is having trouble too.. seems a bunhc of 2011 users early on complained of low mileage when the def tank didn't work properly.
when was the last time you filled the DEF tank?
Hotshot
Joined: Nov 2000
Posts: 11,591
Likes: 14
From: Pflugerville, tx
Wish I could say that is the problem. I had my Fuel filters changed at the Ford dealership when I started seeing my MPG dropping. Still no improvements, I check the computer for DEF level regular, My truck uses 2.5 gals of DEF fluid just about every 1000 or so miles when towing, maybe this could be some of the problem? Whish I could find a solution, if not I might need to buy a fuel station.
'when you saw the mileage dropping.. '
when was that ( miles on vehicle) ?
I don't have any silver bullet answers, I am just asking to help collect info that others might need..
2.5 gals def/1000 miles towing also indicates lots of fuel being thrown down.
Freshman User
Joined: Mar 2013
Posts: 31
Likes: 0
MPG
what does your tailpipe look like? sounds like you are throwing fuel down there. stuck injectorish (haven't heard of that on the 6.7's but you never know)
'when you saw the mileage dropping.. '
when was that ( miles on vehicle) ?
I don't have any silver bullet answers, I am just asking to help collect info that others might need..
2.5 gals def/1000 miles towing also indicates lots of fuel being thrown down.
'when you saw the mileage dropping.. '
when was that ( miles on vehicle) ?
I don't have any silver bullet answers, I am just asking to help collect info that others might need..
2.5 gals def/1000 miles towing also indicates lots of fuel being thrown down.
Mountain Pass
Joined: Feb 2013
Posts: 146
Likes: 21
My hand calculated is usually pretty close, it's between .3-.5mpg lower than what the screen says. I think that's about what it was before I tuned also, if I remember right.
Senior User
Joined: Nov 2004
Posts: 183
Likes: 0
From: Denton, MD
Dunno about these issues but I have a 2012 F-350 6.7 4x4 crew lariat and normally get about 17.9 (hand calculated) running about 70-75 36 miles each way to work anbd when towing my 38' 5th wheel coming in about 13,500 lbs I'm getting about 11-12 depending on terrain. Can't complain at all compared to my '12 6.2 gasser!!
Fleet Mechanic
Joined: Aug 2013
Posts: 1,313
Likes: 19
From: Louisiana
Yeah I will definitely back up 2ndstrokes claim of getting that kind of MPG. I can get that kind of MPG going 60 UNLOADED on the highway, Hand calculated. The computer will say that it's even higher, but 23 MPG is possible ALL day on these trucks. Comparing everybody's truck's MPG is only good for a mean. Wheels, tires, lifts, fuel, road quality, tuners, weather, weight in the truck, all these things play a HUGE difference in fuel mileage. I don't understand why this has to be a pissing contest. Somebody asked for fuel mileage, it was posted. If you don't believe his MPG, then PM him, not try and blast him for what you think is skewed numbers.