1stTimeAround

Alright guys, I've listened to all the talk about high mpg, I'm just throwin' this out there for anyone else that may be in the same boat as I am. Wondering why my MPG is so low?!

My daily commute is 14 miles each way (28 mile round trip), and pretty much daily I take 2-4 1.5 mile trips to take my kids to ball practice and what-not.

Over the last 6 mos. my mileage is consistently at 13.5 MPG(hand calculated). I have tried using the fuel additive mixture, I drive it pretty light as is, and still don't see how many of you are getting the enormous difference in mileage than I am. My commute is broken up by 4 stoplights and 3 toll booths, so I am never driving for more than 4-5 miles before having to slow to 10 MPH to get through the toll or a complete stop at a light.

I haven't taken the truck on a long road trip without towing the camper, so I don't know what the highway mileage is. When towing, I am getting about 9.5 MPG(hand calculated) which I think is terrible. I am very disappointed with that number.

The only change from stock is the tires and wheels, I now have 325/60/18 on the truck. I knew when I put them on that the mileage would be affected, I just didn't expect this kind of hit. I did put a 2" leveling kit so the tires would clear.

Understand, this post is not a complaint about my mileage! I knew what I was getting into. It is just a post to let other folks know that not everyone is getting 18-20 MPG, and that there is nothing wrong with your truck if you aren't.

JAXFL1

1stTimeAround,

I agree with you and it hurts. I've have also listened to all the talk about high mpg. I have also wondered why my MPG is so low, clean air & oil and Fuel filters every 5000 miles. My daily commute is 7 miles each way (14 mile round trip), and pretty much daily I take a couple of half mile to one mile trips to what-ever, mall, stores, etc...

My mileage is consistently at 14.5 MPG(hand calculated/computer). I also drive it pretty light, I am not the first one across the intersection, and still don't see how some of the folks are getting the High milage that is claimed. My trip also has 4 stoplights and 2 miles of freeway driving at 5am, so no rreal traffic to slow me down, so I am never driving for more than 2 miles before having to make a complete stop at a light.

I have taken the truck on a long road trip without towing the camper and get in the 17-18 MPG on these trips. When towing, I am getting about 10.5 MPG(hand calculated/computer) which I think is terrible but better than the last Ford that got 8.5MPG. I have been very disappointed with the numbers very sence I bought the truck in 2003.

The only change from stock is the tires at 285/17.

reidry

I agree there is probably nothing wrong with your truck, many of the modifications you've made are affecting your mileage.

I just returned from a 870 mile trip. Traveled from Florida up I-95, through Georgia into South Carolina and took 26 up to West Columbia (Cayce). Unloaded on the way up at 70-72 MPH she got 21 MPG. On the way back I pulled a 30' Pace Shadow GT Enclosed Car Trailer at 65 MPH and she got 15.3 MPG.

My local commute is 28 miles door to door, 20 miles (71%) is highway. Run around town and pickup my daughter during the week and I manage 19-20 MPG on weeks where I just stay local.

Mileage is all hand calculated.

My truck is basically stock with Line-X and rear wheel liners. I run the stock tires inflated to 70 PSI and I'm stock height.

These "leveling kits" create a bigger profile with more air passing under the truck therefore creating an even less aerodynamic brick. The 18" rims you're running may be heavier than stock, those tires are definitely heavier and the extra width creates a lot of rolling friction.

Ryan

toynrnd

I just completed a 2200 mile round trip to Wisconsin. We had my 2006 Megacab, a 36' gooseneck trailer, a CJ5, a CJ7, and a Powerwheels Jeep on the trailer. Total weight of this setup on certified scales at White's Truck Stop was 22,900 lbs.



We went I-64 from Chesapeake, VA to Louisville, KY then I-65 to Chcago and on to Elkhart Lake, WI and back the same route. We drove between 65-70 mph. Hand calculated mileage averaged 9.8 mpg. Best tank was 11.5 mpg, worst was 9.0 mpg. Overhead computer was showing 1-1.5 mpg better. I am very happy with the results considering our 5.9 gas powered Durango pulling a single Jeep on our single car trailer gets 10 mpg.

Foxborough

Just a quick point. Have any of you folks checked your miles against the mile markers? Hand calculated, I could get close to 18 empty, 14-16 range combined and 11.5-13.6 towing a #6000 boat (I normally cruise 70-75mph). I have stock tires and They show more miles than actual. I have to multiply my odometer by 0.987 to get actual. I have read on other posts that the miles driven could be the other way. You could possibly driving farther than your odometer is displaying. Just reset my trip meter when passing a mile marker and write the mile post down, I could tell in 10 miles something was slightly off. I am happy with mine, use to drive a Suburban. The Suburban never got past 16 empty, 9-10 towing and 12-13 city. JMO

PanteraGSTK

Any time you put on a bigger tire/rim it will affect your milage. Bigger tires means inaccurate speedometer, which means MPG isn't accurate because your trip and odometer are off by whatever percentage your new tire is larger than stock. So thats one reason.

I really love reading these posts because I drive a 1500 v6 Ram that is supposed to be "fuel efficiant". Well, in town I get 11mpg or so. And on the highway between 70-75 I get 16.5mpg. When I find a truck I'd be happy to be driving a 4wd solid axle CTD that gets the same milage as a 2wd v6 gasser. 100 more HP than my engine and 400 TQ more, what would you rather have?

artesian

Good post. I also see an average of about 14 MPG on my 28 mile round trip dail commute. Never tow much and on long trip I never see anything higher than 16 mpg.

robert chilton

Guys with short commutes will not get good MPG. The motor has to be up to temp to get the milage. This is because fuel is being wasted trying to warm up all that cast iron. My truck gets 16.5-18.5 on average running empty. Better on the country highways. Twice I have gotten 24.5 MPG. That is not normal but it can happen. I hauled a 2k lb trailer to TX and averaged 16 MPG at 75 MPH. I returned hauling my 95 and got 10-12 MPG running between 65 and 75 MPH. Every tank other than the first has been hand calced. The quad standard box has gained my about 1.5 MPG running empty. In the next couple weeks I am going to get my 5ver that will put the truck near max wieght. I will post back the MPG on that trip.

Donut Gestapo

Well, since getting the reflash my mileage is about where I expected it.

My daily drive is all around town. The day is about 25 to 45 miles depending on destinations, etc. with about 3 or four shutdowns. If I don’t get on the highway for an entire tank I will get 14.1 hand calculated. Not bad for a big truck. I do make an effort to make sure the engine gets to operating temp before the first shutdown of the day.

If I do mixed driving I get 17.7 hand calced with 50/50 city/highway. Again, not bad for a big truck.

I don’t have the ability to do all highway driving (actually only once and I got 18.7, but that was before the reflash). But, I have reset the overhead display while on the highway with the cruise control set. At 55mph (yes the actual speed limit) the overhead displays in the 26’s. At 60mph it displays in the high 23’s or low 24’s. At 65mph it reads in the 22’s and at 70 it reads in the high 20’s. Now, I know that those are display number and they may low or, more likely, high. Still, those are numbers that are more than acceptable.

I would have to say all these numbers are right around where I should expect them. My ½ ton Chevy got 12 to 13 mph around town and, on a good day, 16 on the highway. So, I have a bigger and stronger truck with about a 10% increase in mileage. Not too bad.

rockdonon

Hi All......
I have a 2000 7.3 4X4 Excursion, and just traded an 04 3500 4X4 SO for a 06 3500 4X4.
All 3 diesels have been very effected by head/wind uphill grades rpm over 2200, and stop in go. Under ideal conditions the Furd gets 18 mpg stock, the 04 got 21mpg (mods: free flow exhaust no cat, afe intake, edge EZ, 2" lift, 315/70/17 BFG.)
The 06 no mods (yet) still new 2,000 mi. so far 16.5mpg.
As soon as I get uphill grades, head/winds, traffic, get off the HWY, or go over 2200 rpms take 4 mpgs OFF for all 3 vehicles.
All miles with GPS and Hand couc.

Thenewguy

I have to say the #1 thing that will kill mileage from my experience is short trips. Mine will get about 2-4 mpg better on say a 100 mile trip than it will on a 30 mile trip. Running from school to home is 55 miles round trip. I've done this for several tanks and mileage is about 16(both school and home are right off the highway too, so there is not much city driving). Took it on a trip to Dallas and back and got over 19 running mostly 75 mph.

Thrust

Hmm,

I just got back from a 1200 round-trip (from PA-KY) and averaged around 20-21mpg hand calculated. The overhead read 23.5mpg. I'm happy with my mileage considering I have BFG 315's. Maybe it's the 3.73's?

DBLR

1stTimeAround,

One question I have is how did you break in your engine as you don’t do it like a gas motor nor do you drive it like one. The Cummins was made to haul/tow heavy weight and not run around town empty during the engines 20,000-mile break-in.

One good way to break in your CTD is to load 1000 lbs or more in the bed and drive it for as long and far as you can on the hwy only stopping for fuel. Also keeping it under 2200 RPM helps out and no jackrabbit starts. BTW, City driving kills the mpg on these engines along with big wide tires.

Even when my truck only had 300 miles on it, I took a 350-mile trip and got 18.1. 95% of the trip was on the hwy @ 70 MPH, empty. With only 1500 miles on it I took a 4700-mile trip from IA to OR with 3 people and about1000 lbs in the bed and averaged 18.35 for the round trip. My worse mpg was 16.5 and best was 20.38. BTW all mpg was hand calculated.

One thing that I feel that helped me get good mpg and engine break in was that on my 4700 trip the truck ran 32 hrs each direction non-stop except for fuel. One more thing I do to improve mpg is to use up to 16 oz of PSD (gray bottle) and 8 oz of MMO in every tank. Also my truck gets its best mpg between 1500 to 1750 RPM’s.

CrazyCooter

Don't forget about A/C. In town, I can watch the overhead drop fast just by turning on the A/C.

I never thought a torquey engine would be affected like that by something so small.

ratat98

This is just a shot in the dark, but I have noticed that my mileage has dropped since they put the ULSD fuel in the stations...I used to get about 21 consistently hand calculated, but since they changed im getting 17ish... and I haven't changed a thing on my truck..

Guess it could be something wrong with the truck, but I haven't noticed any power drop or anything of the sort...