So if the Honda referred in http://www.carpages.co.uk/honda/hon...;echo=868369562 gets 92 mpg (if you go to the specs it shows combined 52 mpg) so say it gets even 70 mpg on the open road and the vehicle weighs 3300 lbs it seems like my 99 dodge cummins should get alot better than 20 on the open road at 65 mph. I wonder what Honda did to their diesel to make it so effecient and could I do those things to my Cummins?

 

Better aerodynamics, lower rolling resistance, less drivetrain friction - all these things add up. The Honda's not built to pull so the cruise RPM is much lower in the engine's rpm range. Also, the Honda has half the weight but 1/3 the engine size. Compare the Dodge to the Ford and Chevy and you'll find it does quite well.

 

For starters, it weighs a heck of a lot less, and it's a lot more aerodynamic.

Just try to put 2,000 pounds of mulch in the back of the Honda.
Or tow a 20,000 lb trailer.

Each is designed for a specific task.

 

wannadiesel: On other posts I asked about lowering my RPM with a overdrive and to improve economy but people came back that the "sweet spot" for the Cummins is 1800 to 2000 so lowering the rpm would hurt economy. I asked if anyone had done a lowering of RPM and only got one response form a fellow who said it didn't improve economy but did make the vehicle ride quieter.

 

This did even better than the Honda.


http://www.hydro.com/en/press_room/f...speedster.html



17 world records
After the trials were over, Opel could successfully note no fewer than 17 new world records for special cars with turbocharged diesel engines in the 1100 to 1499cc class, including:
An average speed of 141 mph over 24 hours (at an average 31.4 mpg)
Top speed of 160.2 mph
Best fuel consumption in Economy run: 111.2 mpg

 

The "sweet spot" issue relates to pulling loads efficiently. That RPM range is where the engine is running most efficiently, so when you're asking for a lot of power it is supplied with minimum fuel use. If you're running empty, the slower you can run the engine (within reason) the better the fuel economy will be. This is because the engine never needs to make much power, so the the fewer fuel injection events per mile the better. Running lower RPM also cuts parasitic losses (the power required to turn the engine and accessories). Parasitic losses don't make up a large percentage of the fuel use when you're hauling a 14,000 pound 13 foot tall fiver around, but when you're running empty they are significant.

 

Kinda like the right tool for the right job. The honda may get better milage but I don't see them pullin a loaded fiver anytime soon. Our trucks get better mileage than I thought they did. I bought mine without knowing the approximate mileage it gets and was mildly suprised when I looked at the overhead computer. Given that our truck have the aerodynamic properties of a brick with wheels, we are getting great mileage.

 

Take all the steel parts off your Dodge and have them re-manufactured out of plastic.
No, Wait,......that would make it a Chevy.

 

Heres what you neeed to do

Go buy a srw 2wd quad cab

Drop her to 7 inches clearance

Put on one of those lil kits you see all of the southern folk runnin around on there lowered truck

Find some company that will detune your engine ( doest take a whole lotta power to actually move the truck)

and you should get better mileage

Now I for one hate lowered full sized trucks. If you want that buy a car

2 unless its a daily drivier or some sort of custome burnt chip where you can flip it from 100hp to 500 hp Ur truck is now useless as a truck

but gosh gee i can get 40 mpg


On a side note. On "Car tech of the future" They had an 03 dodge cummins 4x4 dually quad cab running 43 mpg certified and runnin on a bio fuel none the less. And basically all they did do was lean out the fuel in the rail and she went like a dream

The truck was for sale for awhile i dunno if its been sold or not

 

Kingofdodge7131
Where in Sacramento can I get someone to "detune my engine"
Where can I get info on the 30 dodge cummins that got 43 mpg?

 

johnr9q,



Your flat bed may be co$ting you some mileage???? As much as you want mileage you may want to consider a custom built topper to set on your flat bed when the camper is not on it. This might decrease the aerodignamic (sp??) drag. Give it some thought and let us know how it works. Also as talked about before, is your truck a manual or auto? A manual could get better mpg and an external overdrive might help as well. just my .002

 

Yeah, the flatbed may cost mileage. On my truck, above 70mph without a tailwind DESTROYS all hopes of good mileage. The wind is just too much to overcome.

Below 70, boost mostly stays below 10psi, but above it takes anywhere from 12-20psi, depending on conditions.

That said, I get 10-15 pulling our trailer (loaded with farm machinery, which is less aerodynamic that our trucks), and up to 19 empty (19 is when I watch my driving, and keep my foot out of the smoke pedal ).

Overall, I couldn't be much happier with my mileage, considering my dad and brother's gas jobs get 11 TOPS (454 Chevy) , and 14 empty (Dad's 6.0L Chevy). I won't even give you their loaded numbers

Chris

 

Boy I wish I got anything like the mileage figures I hear. The best my rig has done is about 15.9 empty and 11 to 11.5 pulling an 8500# trailer. How do you do it? More important, How can I do it?

 

well first watch the tv guide for "car Tech of the future" usually fall upon it every 3 monts or so.

I believe most the info can be found somewhere on this site

http://www.drivetosurvive.info/

I think i mistaked earlier The 42 was on a 03 2500 4x4 the 3500 dully has a top of 28


not really sure where you would get a de tuner. I would think though that one of the companies that custom burns chips could burn one to make the truck think its getting more fuel than it is. But unless you running some sort of lub increaser i wouldnt do it. That is how they got the 42 though. Ran a special blend of b100 and then leaned out the fuel rail. using basically what a 2.4 liter would ( talked the one of the guys that worked on the truck on the biodiesel powered by infopop fourms. but its been a while so dont quote me

I would think that if you stay the speed limit and not try to work the truck super hard to where she was runnin easy and you kocked down the fuel it would work. Wonder why companies dont offer something of this sort?

 

Yea I got 40 MPG on mine once too. The speedo was acting up and jumping all over the place and when I came to a stop at Idle I was regestering 90-100MPH and clocking miles to boot. The gas mileage was great til I fixed my speedo. There was a bad ground on my alt. Now I get 18 MPG avg. I'm still happy with that. Maybe those guys need to check their speedo for accuracy.