2nd Gen Non-Engine/Transmission fuel mileage

[fox]

Since a few members are always asking, I thought I would post my latest trip report.



We hauled a car about 900 miles on an open trailer--guessing about 6,000 lbs-- from Illinois to up-state NY .

Going we had some tailwind and ran 55 to 60 most of the trip.

Coming home with out trailer we ran 70-75 into the wind.



With trailer, the numbers show 16. 0

Empty we did 17. 5.

I am positive that if we went 55-60 empty we would have seen 20-21. I can do it locally. These trucks like fuel at RPM.



BTW, the wife drove while I slept for 3 hrs.

Her comment, when I woke was " This is fun to drive I really like the power"

I hope we don't fight over it!!!



PS. I didn't tell her the comp was only on 2-2.

 

[SmokinJoe]

Originally posted by fox

With trailer, the numbers show 16. 0

Empty we did 17. 5.

Memphis TN, to Michigan.

13,000 lbs gross per CAT scales

my truck/brother/tools/2 axle trailer with Dodge Neon on it



70 mph to Michigan we got 16. 98 MPG!



I drive 60 mph to work 130 miles round trip, I get 24 mpg... I have threatened my wife that one weekend I am going to drive to Texas, to see how far I can go on one tank NON stop.

 

[JCyrbok]

Spring of 2002. Ann Arbor Mi to Atlanta Ga, aprox 700miles equals 20. 5MPG. This was empty, no trailer. Fuel needle was just starting to flirt with the "E" on the fuel gauge when I pulled into pumps.



These trucks are great on fuel! No one at work believes me when I say I get aprox 17mpg combined driving in a 7000lbs truck!.



J-

 

[dflack]

fuel tank will win

Smokin' Joe - In considering a MPG run, remember that if the Rules state "non-stop" you cannot outrun your bladder. I had this great idea once upon a time. Got in my truck and started driving. Think about it - if you're trying to burn about 32 gallons of fuel at 20+ mpg, thats 640+ miles. To do 20+ you will have to keep your foot out of it, 60-65 mph. If you average 60 mph, that's nearing 11 hours.



No offense, but I will bet on the truck.

BTDT

 

[fox]

Another thing that I noticed was that It appears the more boost the better the mileage. That is IF nothing else changes.



Have you guys noticed improved mileage in hills?

My 95 loved the hill. Numbers would go up by 2-3 mpg.

A trucker explained it as "the diesel injection pump does not inject fuel while coasting and also when climbing a hill it runs the boost up, which makes the combustion process more efficient.



This 24 valve does not like rpm if you are after mileage.

The 12 valve was less sensitve to rpm.

 

[illflem]

fox, more boost=more fuel, your mileage diminishes with higher boost. Simple law of physics.

27 mpg has been my best empty with 22-24 mpgs consistently, but that's with a 12 valve.

 

[MarkF]

Just drove from MA to South Florida and back. Figured mileage on all tanks of fuel by calculator, worst was 14 best was 18 average speed 80MPH when I drove 75MPH when Wife drove. Unloaded going down (cept family gear) maybe 800 lbs in the bed coming back. Oh yeah, comp on 3X5 whole way. The wife loves driving the truck with all the get-up-and-go the comp gives it.

Beuty was we only had to stop for fuel three times each way and still had 1/2 tank left at our destination. Of course we had to stop other times (bladder, 8 week old baby in back seat, etc... . ).

 

[fox]

I know the boost is from heat which is from fuel/load. But, doesn't the boost increase the efficeincy?



How do you explain the increased mpg in my old 12valve in the hills.

Not an argument , just wanting to learn. Hope this doesn't go like the transmission wars!!!!



Also, it would be interesting to see what setting for the comp is best for light throttle/ mileage. I won't accept OFF.

We also noticed the fuel we bought in Indianna smoked more than Illinois.

 

[dflack]

what about mystery 2200rpm

There was also a thread a while back claiming that the programming somehow increased the efficiency of 24-valves starting at about 2200 rpms. That thread sort of died without anyone providing any technical support or any real world data at 2200+ rpm. any more comments on this efficiency claim... ?

 

[illflem]

Here's an article that explains the relation between boost and diesel fuel economy, near the bottom.

http://www.highwaystarmagazine.com/yourjobfeature.cfm?ID=144



I'm sure if you do a search you'll find a ton of info on the subject.

 

[jponder]

Originally posted by illflem

Here's an article that explains the relation between boost and diesel fuel economy, near the bottom.

http://www.highwaystarmagazine.com/yourjobfeature.cfm?ID=144



I'm sure if you do a search you'll find a ton of info on the subject.

Ifflem you and I used to talk some about mileage. Tell me about what all you did for max mileage. I posted a 26. 5 over 500 miles running slow 51MPH avg using a constant throttle cable. I never tried again because it was hard to sit in the truck for 10 hours on a trip I knew should take 8. ******* in a cup and throwing it out the window is part of it if you are going for max mileage

 

[jponder]

Re: fuel tank will win

Originally posted by dflack

Smokin' Joe - In considering a MPG run, remember that if the Rules state "non-stop" you cannot outrun your bladder. I had this great idea once upon a time. Got in my truck and started driving. Think about it - if you're trying to burn about 32 gallons of fuel at 20+ mpg, thats 640+ miles. To do 20+ you will have to keep your foot out of it, 60-65 mph. If you average 60 mph, that's nearing 11 hours.



No offense, but I will bet on the truck.

BTDT

Like I was telling Ifflem. It helps to have a sliding rear window and the bed of your truck needs to be sprayed out when you are through

 

[dflack]

enough already!

jponder - don't you know that your truck is less aerodynamic and therefore less efficient with the window down ?? !! ??



... 10 hours at 51mph? you MUST be retired (or just plain nuts!)



figure the savings at 25 mpg vs. 20 mpg = about 5 gallons of fuel over 500 miles. 5 gallons at 1. 50/g = $7. 50 divided by 2 hours = less than minimum wage. Is your time worth more than your ego (and your sanity driving in slow motion!!)

 

[Jumbo Jet]

Drove from Grants, NM to Hinton, OK on I-40 non-stop, 79 mph on cruise - just over 7 hours - stiff tail wind with camper shell on truck - averaged 24. 5 mpg - 570 miles. Bladder made me stop! Still had 10 gallons of fuel left.

 

[illflem]

jponder, My 27 mpg run was 860 miles from Billings MT to Minneapolis on one tank! Low fuel light was on but it only took 32 gallons to fill it. Basically all downhill or flat with a strong tailwind.

Unlike you I stopped at three rest areas to pee.

Kept my 12 valve rpm at 2000, about 72mph with my foot, no CC.

Don't know why but my 2500 has always gotten excellent fuel economy, worst mileage was 15 mpg with an 1800lb camper pulling a 6k trailer though the Rockies.

 

[jponder]

Re: enough already!

Originally posted by dflack

jponder - don't you know that your truck is less aerodynamic and therefore less efficient with the window down ?? !! ??



... 10 hours at 51mph? you MUST be retired (or just plain nuts!)



figure the savings at 25 mpg vs. 20 mpg = about 5 gallons of fuel over 500 miles. 5 gallons at 1. 50/g = $7. 50 divided by 2 hours = less than minimum wage. Is your time worth more than your ego (and your sanity driving in slow motion!!)

Not the sliding rear. Maybe Nuts, but when I'm not looking for mileage I only go 65 - 70. I mean its not something you would do everyday but its kinda cool to look at the extremes of the trucks whether its 1/4 mile times or max mileage. Hell if I thought I could break 28 I'd go 45. When I get bigger tires I will be able to turn less rpm at higher speeds so I look forward to that. So far as money, I could care less about the money I was checking mileagfe just for the enjoyment of another wow. I have towed a 28K dozer, My truck is very quick and it got 26. 5 MPG WOW! either you get it or you dont.

 

[jponder]

Originally posted by illflem

jponder, My 27 mpg run was 860 miles from Billings MT to Minneapolis on one tank! Low fuel light was on but it only took 32 gallons to fill it. Basically all downhill or flat with a strong tailwind.

Unlike you I stopped at three rest areas to pee.

Kept my 12 valve rpm at 2000, about 72mph with my foot, no CC.

Don't know why but my 2500 has always gotten excellent fuel economy, worst mileage was 15 mpg with an 1800lb camper pulling a 6k trailer though the Rockies.

Man that is awesome iflem. My michelins have 72K on them and when I get new ones I think I am going with that 2 skyjacker and some realy tall 19. 5s and I can wait to see what I can post on a real slow long trip. Yes that foot thing is hard a cable makes it sweet

 

[dflack]

I get it

jponder - yes I get it... really frosts my fishin' buddy that I get low 20's in my 6000 lb truck and he gets about 17 in his lexus.