Fuel Mileage - Be Honest

[Doc]

I'm back to looking at buying a new truck. I don't want to get into a flaming war about Dodge vs Ford vs Chevy, so let's noto go there. I'm pretty much set on a Cummins if I get anything new, anyway. What's going to be the deciding factor is mileage. I drive a lot and the difference in 3-4 mpg can mean a good bit of money in the long run.

I would greatly a appreciate any information you folks may have on the fuel mileage of the new 5.9 Cummins. I've had some guys tell me the get 22-24mpg and I've had some tell me 10-12mpg. And I've had more than one tellme they get 28-30mpg.

If any one would please pass on their fuel mileage I would greatly appreciate it. If you want, just send me the numbers and I'll do the math. Either way, I just need to data to help me make a decision.

 

[rubberfish]

18 miles per Canadian gallon.
I don't know by how much bigger they are.

Your 55gal drum is only 45gal here.
That'll give you some idea I guess.

This mileage is combined city+hwy unloaded.

 

[lschultz]

From 18 to 21 running on the highway. Mileage is down on the newer ones.

 

[***]

I average about 16-18 around town on both mine. If I baby it and watch the overhead on the highway, I might be able to go as high as 20mpg. It's just not how I drive... I usually have it pushed down pretty far and get around 16-17 mpg. I really don't know where these people come up with 23 or more. I can't drive like that.

 

[argve]

I typically turn about 17-19 (US MPG) with my mix of highway and city level driving. Now if it's all highway running 70-80mph then I can turn out 23mpg. Now towing it's 15-19 on the highway (10klbs 31ft TT) depending upon lay of the land. I always drive between 70-80 on the highway even while towing so...

 

[Greenhornet1986]

I havent tracked my mileage every tank since I bought my truck last year. But, from what I've seen, hand calculated, I am getting 16-18 or so around town, and 19-21 on the highway(highest I've ever seen is 23mpg on a trip, hand calculated). That was on a totally stock truck; now I have a straight pipe, swiss cheesed air box, and a rokktech sensor. The mileage on this tank isn't going to be worth a crap, since I just had the straight pipe put on, and I love the way it sounds. I'm hoping it goes up a little bit, but am already thinking of selling the rokktech sensor(just for financial reasons).

Some people that tell you 28 or so are probably going by their overhead monitor, and more than likely have a box of some sort on them. These will throw off the overhead monitor, which is not accurate anyhow(well, not too close, but I use mine to figure out where to run to get the best mpg).

 

[steved]

I get anywhere from 16mpg (all city) to 23mpg (all highway).

I have heard the 3rd gens claim anywhere from 10mpg to 27mpg...I guess you either get a good one or a bad one...

They also take around 30k to break in...

steved

 

[MMeier]

Empty and weighing in at around 9k or so, I get about 17 , single car trailer and "average' vehicle on it about 15-16, 40' Gn and a container or two on it,(28-30k#) 8-9.

 

[killer]

18 miles per Canadian gallon.
I don't know by how much bigger they are.

Your 55gal drum is only 45gal here.
That'll give you some idea I guess.

This mileage is combined city+hwy unloaded.

An Imperial gallon is 4.54 litres. A U.S. gallon is 3.79 litres. Multiply miles per Imperial gallon by 3.79, and divide by 4.54 to get miles per U.S. gallon.

I think.

The last time I checked mine, I got about 17.5-18.5 (U.S. gallons). My truck had 34,000 miles on it at the time, Juice was set on level 3 with low boost fueling at 5, and speed was 70 MPH.

 

[Locomotion]

Pretty much all I ever do is tow a car trailer. These numbers are on flat highways:
I averaged about 13.5-14.5 with an open trailer all weighing about 6-7,000lbs
Went to a 26' Pace weighing about 10,000lbs and lost about 4mpg - 9.5-10.5.

Truck is a 2004.5 Quad Cab, dually, auto 3.73 gears and a fiberglass topper.
As mentioned, the older trucks will get a little better mileage. But I've been doing some research on how to get a little back.

Amsoil synthetics front to rear. I did see a slight operating temp decrease and slight mileage increase in my 1992 Club Cab dually when I switched. I went to synthetics on the 2004.5 before it had 10k on it, so it was still breaking in. I don't know how much it helped this time, but I'm sure it did.

Year of the truck and options will make a few mpg difference.

The overhead computer can vary quite a bit. It even varies in accuracy between hwy/city and towing/not towing. From what I've heard, anything over 20mph on the highway, empty, with a 3rd gen. Cummins is very good. Much over 20, I would be skeptical. 60-65 mph cruising seems best for economy.

 

[CUMMINS05]

Yeah Okay, I am driving a 2005 Cummins 5.9L. When I had 5" turbo back exhaust, and AFE Stage 2, running Mobil 1 Devlac I was getting 24mpg US, this is the honest truth. This seems to be where it ends as of yet. I have put in the the Techni-Cooler, & the Six Gun w/Speed Loader. I have no Change in MPG, just wicked power on tap. I am positive with a T Converter change and tranny upgrade I will improve the MPG. I also have a Industrial Injection Super Phat Shaft 62 Silver & ATS 2 Peice Pulse manifold sitting here waiting to go in. I dunno how that will affect the MPG. I know about the power. ... But those guys in the high 20's I would like to see what they have rigged up, because I would love to see it.
Cummins Rocks - Never a question.

 

[Monty3500]

2003 SO dually, 6 speed, 35x12.5's engine is 100 percent stock

under 50 MPH i average around 16
over 50 (usually highway 65-70 mph) 13.9-14.2

 

[cdennyb]

incredible now!

OK, Believe it or not, here it is.

Highway empty in the summer: about 26-28 @ 55-60 mph
in the winter it drops a little: about 24-26 @ 55-60 (maybe the water on the road or something.)

I run all synthetic gear lube enhancers in the trans, rear end, and fuel additives in every tank of fuel. I drive easy and have 4" into 6" stacks without any Cat or ****. I have a Banks 6-Gun with the Speedloader set on level 4 and around town you can pretty much drop 5-8 mpg off those numbers.
Stop lights suck.

My last set of tires (The original General Ameri-Tracs) were on the truck when I got it at 32,000 miles and I just put a new set of rubber all the way around and I'm at 133,450 now. That's right! I got over a 100,000 miles on those tires and they were on there when I bought the truck!

We occassionally pull a kinda heavy car trailer and the mileage drops to around 16-18 loaded.

So there you go.

db

 

[Mike]

I knew I should have bought a Dodge, you guys are getting nearly 30 mpg and over a 100K on a set of tires.


Those Dodges absolutley ROCK!!!!!

 

[MMeier]

Whats so funny there Mikey!!??