How to get better fuel economy w/your diesel
After talking to hundreds of folks across the country I found that the average diesel owner gets 15-16 mpg.
Also what I have found is the "posted speed limit" has everything to do with mpg.
If someone lives where they hardly drive over 60-65 mph unloaded they will most likely brag that they typically get 19-20 mpg.
Someone who drives 75-80 mph will most likely be getting 14-15.
I have personally taken and compared side by side a "broke-in" 05 Cummins and a 05 Power Stroke.
What I found was at if I maintained a speed of 65 mph I averaged 18 mpg. Once I increased my speed to 75 mpg I averaged 14 mpg. SAME TRUCK... 4 MPG DIFFERENCE.
The Cummins actually dropped less mpg than the Power Stroke with the increased speed and I contribute that to the fact that the Cummins hits it torque band faster at lower rpms.
SO IF YOU WANT TO BRAG ABOUT HIGHER MPG "DRIVE SLOWER!"
(I did however talk to a guy the other day that installed a performance module called the Workhorse and says it increased his 05 PS MPG from 15 to 20. He also said towing a boat he still got 17mpg. He said he bought it at www.888luvdiesel.com)
Also what I have found is the "posted speed limit" has everything to do with mpg.
If someone lives where they hardly drive over 60-65 mph unloaded they will most likely brag that they typically get 19-20 mpg.
Someone who drives 75-80 mph will most likely be getting 14-15.
I have personally taken and compared side by side a "broke-in" 05 Cummins and a 05 Power Stroke.
What I found was at if I maintained a speed of 65 mph I averaged 18 mpg. Once I increased my speed to 75 mpg I averaged 14 mpg. SAME TRUCK... 4 MPG DIFFERENCE.
The Cummins actually dropped less mpg than the Power Stroke with the increased speed and I contribute that to the fact that the Cummins hits it torque band faster at lower rpms.
SO IF YOU WANT TO BRAG ABOUT HIGHER MPG "DRIVE SLOWER!"
(I did however talk to a guy the other day that installed a performance module called the Workhorse and says it increased his 05 PS MPG from 15 to 20. He also said towing a boat he still got 17mpg. He said he bought it at www.888luvdiesel.com)
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I'm new to the group, and have a few questions for everyone. Currently I own a quad cab 2500 4x4 diesel Ram and get an average of 14.2MPG with a highway speed of 72MPH. Can anyone tell me from experience how much better fuel milage is switching to a synthetic motor oil? Also can anyone tell me how much better the fuel milage is when using a cold air intake on hte Cummins engine? These are two options I am considering to try to get my MPG to around 18 without easing my foot on the gas pedal.
Jeff
kcram - Pickups Host
I did this after test driving a 2500 Dodge cummins 6spd today and found it very disheartening to be running at 2500 rpm at 75 mph. The Rep at Dave Smith Motors i Idaho told me about the option and my internet research seems to be pretty positive, makes sense if you got 11 gears like a semit truck your engine runs more efficient and thus better mileage. the add on is 2900.00 per the dealer. Any thoughts? anybody running one presently? I do alot of highway driving, rarely tow and want the engine to be relaxed going downt he interstate.
Do you have a 4.10/4.11 gear ratio? 2,500 rpm sounds about right for 75 mph with that ratio. I had an F-350 with 3.73's in it and it ran around 2,100 rpms at 75 mph. I'm afraid that if you go with an overdrive unit, your highway performance will suffer. Turbocharbed diesels need some rpms to get the turbo spinning fast enough to create boost, which in turn builds HP. Find out the overdrive ratio, is it a 15%, 20%, etc... Reduce your engine rpms by that percentage to figure out what your engine speed will be at a given speed in 6th gear. Then get out on the road and try driving in 6th gear with the engine near that rpm. You'll probably want to do this on a not so busy road since you'll probably be driving slowly. Then roll into the throttle. If the truck has plenty of "get-up-and-go" to it, then the overdrive may be an option. I'm betting the engine won't be spinning fast enough. I know how my F-350 drove at 1,600 rpm in 6th gear, even with a chip.
Another option is to just regear your axle. I think that would be considerably cheaper.
here's a reference link: the exact ones I bought:
auction from the guy I bought from
..I couldn't agree more.
..doing 55 mph (absorbing big time nasty looks from many citizens), my diesel will turn in that same figure in mpg. Increase to average citizen speed and fuel efficiency heads for the cellar.
..so I plan ahead, drive 55 and try to avoid eye contact.......
all the best, ez
kcram - Pickups Host
Col1 Cumulative Miles Travelled
Col2 Actual Miles Travelled
Col3 Number of Gallons
Col4 Miles/Gallon
Col5 Price/Gallon
Col6 Fill-up State
Col7 Fill-up cost
Col8 Comments
Col1 Col2 Col3 Col4 Col5 Col6 Col7 Col8
389.1 389.1 22.20 17.53 $3.16 CA $70.13 Mostly freeway at 80MPH
640.9 251.8 14.00 17.99 $2.86 OR $40.01 Montain, Coast and freeway
1003.2 362.3 17.07 21.23 $2.73 OR $46.59 Mostly freeway at 65MPH
1352.2 349 17.69 19.73 $2.99 WA $53.04 Mostly freeway at 70MPH
1702.8 350.6 16.97 20.66 $2.84 WA $48.18 Freeway, mountains, traffic
2143.6 440.8 22.24 19.82 $2.79 OR $62.02 Mostly freeway at 70MPH
Average MPG 19.49
These numbers are based on a round-trip journey based on driving up I5 from CA into Vancouver BC, and then back into CA. This includes moutain passes in northern CA and southern Oregan, as well as driving from Vancouver BC into Whistler. Note that I haven't included the last fill-up here, since I haven't filled up the tank yet!
Some points of interest... diesel is way much cheaper in OR & WA. In fact I think that us Californian's are getting ripped off. I'm not sure why diesel is so much more expensive in CA than the other states. Any ideas? Would be interested to hear what others are paying in their locale.
The mileage numbers are based on using the tried and tested method of Miles travelled divided by number of gallons. I haven't checked the onboard computer... but I don't know if I would necessarily trust it.
Can anyone also recommend a good light truck tire that will help get good mileage? I'm never off road, don't tow anything, and don't usually have a very heavy load. I do, however, need something that will get me through wet roads, snow, and ice, without costing a fortune. I'm trying to save money, not just shift the spending from gas to tires.
During the trip I only noticed a couple of places that had diesel less than the middle or premium grade of gasoline. I didn't see a place that was cheaper than regular.
in response to Farmboy4, have you considered taking a look at Biodiesel (e.g. biodiesel.org) and then seing if that is cheaper than #2 diesel in your area?
Also, if you go to the AAA website at www.aaa.com, click on the Automotive tab. In the upper right side of the next window you'll find a spot to click on for fuel prices in your area. Here's a comparison of stations that sell diesel within 10 miles of me in Glenside, Pa.
Brand Regular Mid Premium Diesel
Hess 2.62 2.72 2.82 2.56
Gulf 2.62 2.80
Hess 2.62 2.82 2.60
Sunoco 2.64 2.80
Texaco 2.66 2.76 2.88 2.99
BP 2.66 2.92
Hess 2.68 2.74 2.60
Sunoco 2.70 2.80 2.77
Mobil 2.73 2.87
Sunoco 2.76 2.84 2.85
Sunoco 2.78 2.80
Exxon 2.90
Gulf 2.86
You'll notice that Hess is the one that sells diesel cheaper than regular. Someone told me yesterday that Hess has their own refinerie so doesn't have to buy it from someone else.
A local diesel repair shop said my fuel jets are probably dirty though I would think a dealer would clean these out before selling the vehicle. I'll try that before looking into a performance chip. I don't need more horsepower, just better fuel economy. I'm looking into the "Workhorse" performance module as a possible solution if I need to. The dealer says it doesn't inject more fuel, just burns it more efficiently.
Here in the Parker CO (just SE of Denver) diesel is between 2.56 and 2.69 depending on what part of town you're in.
Thanks.
Thank you :confuse:
I have been reading comments from all you guys for at least 8 years about your diesels. Well welcome me to the club. I'm ready for some advice. By the way I named her " Lucille" after lucille ball
I will share with you what I have learned about mileage on the truck you mentioned. I have driven a 2001 F250 with the 7.3 P-stroke for 4 1/2 years.
You cannot go by the mpg readout for the short term. It can be fun to play with and may be used as a guide but it is not accurate. Certainly don't trust it to accurately tell you how much further you can go without fueling! You can reset it by pushing both buttons at once while in the mileage mode. Did you know it measures temperature and distance to empty as well as mileage? Toggle to the different modes by pushing the button on the left side. It can also be set to measure in metric.
The only way to get an accurate reading for your mileage is by carefully filling the fuel tank all the way to the top of the filler neck until fuel no longer runs down. Pumping diesel is not unlike pouring warm beer - lots of foam. Ford has never chosen to put a large filler hose on the pick-up tanks like I think Dodge does. Completely filling in warm weather will take about five minutes after the filler starts to automatically shut off.
Anyway fill it up into the filler neck until fuel is w/i 1/2 inch of the cap and stays there. Drive until you have used up 3/4 or more of your fuel. Fill up the same way. All the way to the top, get past the foam! Use a calculator or pencil (God forbid!) and divide the gallons into the miles.
Do this for every kind of trip for a year and you can see what your truck is really doing.
These trucks do much better on the highway than in town. They will run like hell but if you want better mileage accelerate slowly, use cruise control and keep your speed down. Wind resistance at 70 mph is twice as much as at 55 mph (as per NPR last week.)
cdb3
kcram - Pickups Host
Here is what I have learned over the past 4 years or so with some experimentation.
First off, let me say, my stock 2002 Ford 7.3 got about 15-18 mpg. I drive 140 miles round trip (all interstate) to work and back so I have had plenty of time to figure out what makes it tick.
Gearing is everything. My truck runs 3.73 rear ends. To the engine I have added a K&N filter and air box. I also modified the front intake behind the grille for better airflow. The stock intake was about the size of a silver dollar and I took a dremel and opened it up. Also, a 4" exhaust made a big difference. The engine had more "snap" and it lets the turbo spool up noticibly quicker. I also have reflashed the computer with a power programmer. I left it at the 60 HP "performance economy" mode. I am not drag racing it and I was going more for mileage. I also reprogrammed the transmission for stouter shifts. As you all know, the stock transmission setting is a little mushy. Also, a set of decent quality gauges are an absolute must. Heres why: The lower you are able to run the boost, the better your fuel economy. I have experimented with different highway speeds and found that with the 3:73's 55-60 MPH equals 24MPG. The faster you go the more boost the turbo produces the lower the fuel economy. At 70 MPH the mileage drops off to around 20MPG. Now, if the gearing were a little taller say 3:08 it would stand to reason that the fuel economy would be better at highway speeds. Conversly, with 4:10's or lower expect the turbo to be building more boost at highway speeds and fuel mileage to suffer.
Food for thought.
".....I have experimented with different highway speeds and found that with the 3:73's 55-60 MPH equals 24MPG. The faster you go the more boost the turbo produces the lower the fuel economy......"
..IMHO, that is impressive fuel efficiency for a 7.3l TD...
well done!!
(this from the left coast: 1.6l non-turbo trucklet.......
seasons best, ez....
:P
I have a 05 Dodge 4*4 HO turbo diesel w/ 14k miles
My first easy add on would be a K&N air filter
worth every penny, aprox cost $60 and you can hear the diesel breath easier after instalation.
After break in period I would highly reccomend full synthetic oil for the motor. The rear end should be synthetic already from the factory. Keeps it cooler and actualy reduces some noise!
Hope this helps
Jake
I HAVE BEEN HEARING A LOT OF TALK FROM PEOPLE ABOUT ADDING A PROGRAMMER TO INCREASE POWER AND FUEL ECOMONY. I'M LOOKING FOR ADVICE ON WHICH BRAND WILL WORK THE BEST FOR THIS APPLICATION, OR ANY INSIGHT AS WHAT IS MY BEST BET
Your take is logical. I don't know if we are buying diesel from refiners in the Middle East or shipping it from home. Good question to ask. I think a lot of the high price is the refiners are re-configuring to produce ULSD that is mandated this year. Some are already selling it, others are in the conversion process. That and the 3 refineries in TX that went off line in Rita did not help. May just be a combination of problems.
thanks
ford and one day we were driving around and checking the
fuel mileage on the on board computor and we coasting down a hill and watching fuel mileage on the computor and we stopped believing what it saying when it got up to 55mpg
so those little gadgets in these truck are a little off,thank,s
Two weeks now with ~500 miles on the clock with mostly city stop and go driving and I am averaging 15.5 according to the trip computer. During a 100 stretch of highway, that went up to 18 driving a steady 70 (cruise).
Thanks
other than the dye the only diffrence is that the on-road diesel is taxed and the off-road is not.
So for example in CA farm diesel aka red dyed diesel can have 500 ppm and more of sulfur vs 50 ppm on the road. In other states the ppm of sulfur is FAR higher. Again keep in mind the 2006 standard will be 15 ppm.
Going up the same hill at 50 mph you might see the mpg gauge read 10 mpg. This could also be correct.
thanks