Strjock81

Last weekend I had the fun of driving in Missouri and Oklahoma with a loaded trailer during one of the worst ice storms of all time. Fortunately I was able to get thru and get back home unharmed. Unharmed except for my wallet that is.

I was pulling a 24' beavertail dual tandem axle gooseneck flatbed with a John Deere 2550 MFWD Cab tractor w/loader on it on the way down, and on the way back, a John Deere 2750 set up the same way. I was running 55-60 the whole way except for where the roads were bad and I ran 35-45 in 4wd for stretches of 40-50 miles. Combined vehicle weight in total was roughly 22K.

Here are some full tank, hand calculated milage numbers--keep in mind this is constant speed driving, no idling, on a stock fueled truck. Most of the time I had to pull in Tow/Haul, on flat I could sometimes pull in OD:

5.7 MPG
6.4 MPG
7.1 MPG (Flatland)
5.9 MPG
6.1 MPG
5.1 MPG
6.2 MPG
6.5 MPG

I was routinely only going about 150-160 miles on a 30+ gallon fill!

I wonder if I had been pulling this load with an 8.1L Chevy what my mileage would have been? 3? Maybe wouldn't have even pulled it.

D.Wiggs

How is that even possible???? (Not doubting you)

I just pulled about 11K so I was grossing about 20K in 4WD @ 75 MPH through the hills of WV and PA and I got a little over 15. I wonder if something is wrong !??!

CRIMPS

I would expect those numbers from a gasser...thats horrible...

2broke2smoke

eee gads ...

that's the worst cummins mileage i've ever heard ...

unless you were towing in 4 low ...

CD in NM

Last week I had my worst at 11.37, I'll quit complaining. We have been having the ice and snow stuff but I haven't been using my 4 wheel drive. I did check out the air filter, had lots of ice, swapped out a dry one and the mileage came right up. So, maybe you were having some of that kind of problem? I am carrying a spare air filter just for that reason, have two of the Amsoil drop-ins. Brought the frozen one in the house, dried it out, celaned it, now it's back in the truck toolbox. I've had that problem before with my other trucks in this type of weather.

CD

redeyedracer

Seems about right given the conditions (high winds) although it does not seem like you where that heavy or high profile...I would expect about 7-8mpg towing what you described with my 04.5...maybe your filter got a little wet/frozen accounting for the rest....

BTW I routinely get 5-7mpg towing heavy (30k+++) enclosed goosenecks when any kind of headwind is involved....and I'm always going slower than 60 (by choise of course) if I tried to push it I'm sure this thirsty little engine could drink more.

Strjock81

I also went out to western IA last Friday and running 65-70 MPH with about 7.5K behind me got less than 10 MPG on every tank.

I made my own BHAF out of one of the new Amsoil EA cone style filters. I guess this could be causing a problem. It is cold air intake though.

The winds weren't that bad on either trip actually, but I had the tractor on backwards, so the whole backside of the tractor and flat glass of the tractor cab was catching a lot of wind. I also might have been closer to 25-26K because I wasn't thinking of the added weight of the loader/fluids on top of the listed tractor dry weight.

KBennett

That is terrible!!

Do you have a boost gauge? I am curious what your boost was.

The worst mileage I ever got was while towing my travel trailer(only 4K pounds) through Montana with a massive headwind. My truck was stock at the time and my boost gauge did not drop below 20 psi unless I was going downhill. I did not calculate the mileage but my overhead said 9.2 MPG and I think it was close.

I hit a bad headwind with my camper on coming out of St. George, UT recently. The cruise was set at 70 and normally the Attitude shows about 35% load and it jumped to 80%. We caught up to all the gassers that had passed me earlier doing 80 but when they hit the headwind I think they were only able to do 60.

Strjock81

I am not running any gauges, but the truck was definitely working harder than I have ever had it working before. I-44 through Missouri is very hilly and a LOT of the trip was foot to the floor climbing hills, then trying to get some speed up on the downhill before hitting the next hill.

I told my wife when I got back that I "Took 10 years off the life of that truck on the trip."

Even the engine doesn't quite sound the same as it did before the trip--not bad, just different, a little looser. Has 43K on it now.

redeyedracer

I have run these Cummins trucks like that for years!!!! They like it!!!! Your tranny may be a different story though???

Jfaulkner

I averaged about 7mpg on the way from Ohio to Terre Haute, IN (Extravaganza) pulling a 40' trailer with an 04 Dodge and a Yamaha Rhino. My average speed was at least 70-80mph due to being late. Keep in mind wind drag has a far greater effect on milage than weight.

RAMRODD

You would have gained about 2 mpg if you had a chip. Then you could have stayed in OD.
You spent a little on fuel. But if you would have hired a semi the bill would have been much larger

buzzard1

You must have a mechanical issue.The worst mileage to date on my 03 was pulling my 23k# trailer(32 ' dual tandem trailer, 100hp 4x4 tractor and batwing) in town for the whole tank with a top speed of maybe 45 and lots of idling was still 8.5 mpg. Hwy towing at 60-65 with a 20k# trailer is from 11.5-14 mpg depending on conditions. It is looking like my 06 is on track to get even better towing mileage.

dodgepower88

I think that your problems are just an extreme circumstance.

My dad's 06 was pulling a 28' gooser with an empty fuel tank on it (12,000 gal), the total height was about 14', and he was going against a massive head wind. He ended up averaging 5.2 mpg. He gets about 16-17 empty so i don't think that there is anything wrong with his truck besides that it had only 2500 miles.

Hope this helps you feel like your not the only one.....

N.Johnson

You can't really begin to complain about mileage on a electronically fueled diesel unless you have gauges. These trucks are totally fueled by the computer regardless of how your foot is planted on the skinny pedal. They (gauges) are not just for the high performance rigs. A boost gauge is first, to tell you how much your right foot is sucking on the tank. The phyro gives you the results of the heavy foot. Hey this is not a know it all lecture, just my own and many others observations on watching gauges/mileage. Our rigs produce incredible torque down low in the rpm band which is all that matters moving weight. More throttle input doesn't help getting that weight up to speed and holding it. I must admit that is the worst mileage I have ever heard of, 18 wheelers get that moving 60,000 lbs. If towing heavy on mainly flat terrain for a baby cummins pulling 20-25K you should get 10-13 hand calculated filling the tank to the top of the neck and don't go by the overhead.