780 Miles + 11,000LBS + 70MPH = 13.2MPG

[Crunch]

I have to say I like that math. I hauled 66,000 fresh water shrimp for a friend from Fort Worth to Douglas, Alabama (a bit NW of Gadsden) in 4 livehaul totes on a flat bed trailer. Cat scale put the total weight at 16,880 without me and my personal gear. The trailer weighed about 2,000lbs, the shrimp weighed about 10lbs, so the totes, two oxygen tanks and water weighed 9,000lbs. I kept my speed at about 69-70 the whole trip to keep the RPMs less than 2000, and on hills I tried to keep them between 1500 and 2000. Sometimes that was tough on steep hills with overdrive off. Except for being conscious of the fact that I was hauling a lot of weight I hardly noticed the trailer was there. The one thing that was noticable was when I would hit rough patches in the road and the water would slosh. I could feel a pulsating as the water went back and forth. Fortunately, the trailer was a brand new 16' Load Trail that handled like a dream. I just bought a Prodigy brake controller (based on the comments I read here) and loved it. First experience with electric brakes. My friend wanted to either use his old, beat up trailer or rent one (with a hydraulic unit on the tongue), but I talked him into buying one instead, since he could use it for years to come and it helps his business to be able to deliver shrimp instead of air-shipping them. I think the totes must have had a lot of wind resistance, because MPG went up by less than . 5MPG on the return trip. With the empty totes the total towing weight was probably about 3,000lbs. Of course, I sped up to between 75 and 80 on the return trip. :-laf And to think that my old gasser F-150 was getting 11MPG totally empty on the highway.

 

[WoodT]

lol. . never heard of haulin shrimp before. .



Thats a pretty good MPG

 

[GWBourne]

i know what you mean... i get 14. 1 on average with my GN hooked up. it weighs 22k and has a LOT of resistance due to a shipping container on front. i dont go over 60 though.....

 

[Cattletrkr]

That is pretty good mileage. My empty livestock trailer weighs about 7K and running empty at 70mph I won't break 11mpg, barey over 10mpg is more realistic. 70mph for me is approx 2200rpm.

 

[Crunch]

i know what you mean... i get 14. 1 on average with my GN hooked up. it weighs 22k and has a LOT of resistance due to a shipping container on front. i dont go over 60 though.....

These totes were barely above cab roof level, but being behind the truck I bet they still stalled a lot of air. It would be an interesting study to compare the difference in MPG drop between weight and wind resistance.

 

[Cattletrkr]

It would be an interesting study to compare the difference in MPG drop between weight and wind resistance.

I hauled a load of trailers for Dad last year. 4 GN's total weight around 22K. I got <7mpg. Pulled it fine, just got lousy mileage. Top of the top trailer measured a full 13'6". The worst I've ever gotten with my stock trailer weighing in at 30K is 9mpg. Weight drags the mpg down, but wind kills it.



I might have a pic of a similar load in my gallery, I'll have to go check. Dad's '03 w/auto and 3. 73's gets 7mpg or less on a regular basis pulling those loads. If he gets to make a run with only three trailers and has a tailwind he can get 8mpg.



Edit: weights listed are GTW, not combined.



Here's a pic of a load of trailers.



Why the lousy mileage???

 

[Crunch]

I hauled a load of trailers for Dad last year. 4 GN's total weight around 22K. I got <7mpg. Pulled it fine, just got lousy mileage. Top of the top trailer measured a full 13'6". The worst I've ever gotten with my stock trailer weighing in at 30K is 9mpg. Weight drags the mpg down, but wind kills it.

Wow! 7MPG is less than 1/3 of the mileage some people can get with their truck when not towing. I think the 13. 2 I got on this run was the lowest I've ever gotten. Maybe a spoiler on the roof would be a good mod to look at when towing tall loads, regardless of weight. I've seen a lot of tractor rigs that use them. And at 13'6" did you have to watch out for low bridge clearances and worry about your high center of gravity?

 

[GAllen]

I've never been so lucky as too get these wonderful mileage numbers with my truck. When towing, I'm at just under 21K lbs combined and run between 65mph(2000rpm) and 70mph(2200) including up hill. I basically get 10mpg give or take, hand calculated. I tow between Los Angeles and Glamis, a couple of hills and good wind most days.

 

[Nate]

I get 14-15mpg pulling Jeep/trailer. Around 14500 lbs truck and trailer. I set the cruise at 2000 rpms which is about 72-73 mph.



Funny thing is I only get 16-17 when the truck isn't pulling something. :{

 

[Dixie Dawg]

16. 1 MPG empty all interstate last week, can only go ~520 miles/tank.



My '05 sucks, plain and simple. I'd give my left'un to have my '01 back. :{

 

[JohnCooper]

Just got back from a short trip from Orange County to Ventura (Lake Casitas) this weekend towing my 7500lb 5vr. Got 12. 5mpg on the computer which hand calcs out low, probably closer to 13mpg. You So Cal guys I'm sure are familiar with the climb back into LA from Camarillo, 2nd gear, overdrive off, foot to the floor!

 

[CHolman]

What's is the differeance between the 03/04 305/555 HO engines and the 600 model engines besides and little bigger turbo, "CAT" and electronic waste gate? I average 19 to 21 MPG and 17 Mixed Driving with my mods on my 305/555 373 gears 6 speed; and the 600's have a hard time, if ever reaching those #'s... ?

 

[GWBourne]

What's is the differeance between the 03/04 305/555 HO engines and the 600 model engines besides and little bigger turbo, "CAT" and electronic waste gate? I average 19 to 21 MPG and 17 Mixed Driving with my mods on my 305/555 373 gears 6 speed; and the 600's have a hard time, if ever reaching those #'s... ?

i have no problem reaching those numbers... . the only problem i have is to KEEP outta the PEDAL!! i know when i slow down to about 65-70mph (2000 to 2200 RPM) and KEEP it there, get in the right lane and let people pass me up... it sucks i know...



when this is done then i see 22 and 23mpg hand calc. cruise on and just let it ride. i go from Camp Pendleton CA to Pima AZ (around 630 miles IIRC) on a tank. low fuel light dings just as i pull into my friends driveway. then i drive around half the next day before i fuel up. i take the 15 to the 10/60 straight into Pima.



Grant

 

[Crunch]

You So Cal guys I'm sure are familiar with the climb back into LA from Camarillo, 2nd gear, overdrive off, foot to the floor!

Once I got north of Birmingham I was driving in the foothills of the Appalachians and had to turn the overdrive off and put the foot to the floor. From Fort Worth to Tuscaloosa it was pretty much flat, straight and bordered by swamps. One cool thing I noticed is that the AC doesn't seem to affect fuel economy the way it does on a gasser. In fact, I haven't really noticed much of a drop at all when using it. Maybe . 5MPG at the most. Hitting those hills, however, made me wish I had a standard transmission for the first time since I bought the truck.

 

[White Ram1]

I just got back from a 500 mile +/- pull of an enclosed 22 foot race trailer with a Ford Crow Victoria in it. I only got 9 MPG rolling at 1900 RPM's, which was about 72 to 73 MPH. I figure the trailer is about 2500 lbs and the Ford was about 4100 lbs, so it was a pretty light load IMO, very poor milage for a 6k or 7k load!



Best empty is about 12 MPG.



It pulls like a dream, but I have been VERY disapointed with the MPG since buying this truck. All I heard and read here about these Cummins was 18 MPG empty, 20 + hauling 25K... . That's all BS, there ain't a shot in hell of my Cummins ever getting 18 empty or even 15 empty let alone 13 MPG with any kind of a load!

 

[White Ram1]

I forgot to mention I was hauling in Southren Kansas, flat lands, not much wind. The Flint Hills were the only elevation change at all and I'm betting there wasn't 20 feet change in a 1/4 mile.

 

[Crunch]

I just got back from a 500 mile +/- pull of an enclosed 22 foot race trailer with a Ford Crow Victoria in it. I only got 9 MPG rolling at 1900 RPM's, which was about 72 to 73 MPH. I figure the trailer is about 2500 lbs and the Ford was about 4100 lbs, so it was a pretty light load IMO, very poor milage for a 6k or 7k load!



Best empty is about 12 MPG.



It pulls like a dream, but I have been VERY disapointed with the MPG since buying this truck. All I heard and read here about these Cummins was 18 MPG empty, 20 + hauling 25K... . That's all BS, there ain't a shot in hell of my Cummins ever getting 18 empty or even 15 empty let alone 13 MPG with any kind of a load!

You don't have the specs of your truck in your signature, but I'd be curious to know what they are. I've got the `03 LWB, 3. 73 rear end, auto transmission, 2WD with no lift or other modifications to the engine or truck except for a CB antenna and an aftermarket bug guard. I don't have the HO engine. I regularly drive fast (80MPH range) and consistently get 17. 5MPG on the highway empty. If I keep the RPMs below 2000 I can get 20-21MPG. The wind resistance from the enclosed trailer probably had a lot to do with your getting 9MPG, but there is something else going on with your truck if you're getting only 12MPG empty on a good day. I've been nothing but impressed with the performance of this truck, including fuel economy when towing.

 

[White Ram1]

Crunch,



I've got a 2005 QC Short box, auto, 3:73's, no mods, all stock.



I have gleened from here it seems the 03's get better MPG than the 04 and 05's. But I keep reading this 17 MPG empty, and unreal stuff like 20 + hauling on the highway and there is NO WAY that can be right based on my hand caculated milage since I've owned it.



I don't have a lot of miles, only 37K miles so far. But my last full tank without hooking up a trailer was 11. 2 MPG. I've never seen north of 12. 5 MPG ever.



I don't want to give the wrong impression, I love the truck, it will pull Fort Knox off the foundation, but the fuel economy is NOTHING like I thought or like I read on here.



Maybe something is wrong with mine???????

 

[Crunch]

I have gleened from here it seems the 03's get better MPG than the 04 and 05's. But I keep reading this 17 MPG empty, and unreal stuff like 20 + hauling on the highway and there is NO WAY that can be right based on my hand caculated milage since I've owned it.

My best over 500 miles was 21MPG, empty. I kept the revs under 2000 and took it easy on a long trip to see what it could do. I think some of the high MPGs have come from people with performance boxes on their trucks. I also agree that the `03s seem to do a lot better than those with the same configurations, but with cats on them. Some people have lobotomized their kittys, so maybe they could provide some insight into their pre and post cat fuel economy. For what it's worth, I couldn't imagine 20MPG while towing anything, but I can vouch for 17-18MPG empty and hand calculated--and that's driving 80-85MPH on the highways. I've got 68000 miles on the truck, so I may post my total fuel economy numbers here.



I am now editing this post to include the total fuel economy numbers for my truck (Note: I just sent the final payment in last week, so the truck is now paid off and I am expecting my title any day now!).



Purchased: 7/16/03

Total mileage at last fill up (06/04/06): 69219. 0

Total gallons of fuel purchased: 4038. 752

Fuel economy over life of truck: 17. 13871MPG



Not bad, considering it includes several towing trips, various road and weather condidtions, and my lead foot.

 

[White Ram1]

Nice lifetime stats!!!!



I can only dream of 17 MPG... . I feel lucky when I get high 11's or low 12's EMPTY! :{



I have considered the kitty cut myself, but I promised myself I would keep this truck stock for some time to compair to my others Diesels. This is the first Diesel I have kept bone stock. (you have no idea how big of a deal that is, I was Banks King of Kansas for many years - R. I. P. Powerstroke) Actually I have kind of gotten used to the quiet exhaust note of factory set up.



Why is my MPG is so bad?????