Fuel mileage

[jhenderson]

I have a 2002, 4X4, HO, 6 speed, 4. 10 gears, bone stock. I am getting approximately 14-15 miles mpg empty and 10-11 towing a ten-thousand pound trailer. Have been back to the dealer complaining about poor mileage and they could find no codes, and told me that Dodge says this is acceptable mileage. My previous truck was a 1992 with a 6BT and 5 speed and I averaged over 20 MPG empty and almost 18 towing my trailer under identical conditions. PLEASE HELP. :{

 

[Cummins Corvette]

Those figures are about right. I'd say that, with the 4. 10 gears, that you are doing quite well on fuel when towing. Mine gets less than 10 towing 4k.

 

[RPetersen]

My mileage was in that vacinity until the odometer went by 5000 then it started getting better. Don't tow anything meaningful, but getting 19-20 around town now at 27000 miles.

 

[GTop]

On my 2001 2500 HO I'm only gettin about 17 MPG when running empty. On my 1992 I was also getting at least 20 MPG.

 

[BigDaddy]

jhenderson,



Welcome to the TDR



You don't state your mileage so I will assume it is fairly new (2002). For my first 10K miles (w/auto) I saw a wide variation in MPG between fill-ups. Winter fuel also drops my fuel economy.



If none of the above applies, you might want to check for a loss of boost. Check the hoses and intake for proper torque.



Hope this helps.

 

[Rogue Ram]

Of course the dealer will tell you the mpg "is within spec"... ... ... that is called "DEALER-SPEAK", which is what they do when they don't have a clue what is wrong and don't want to pay to find out.



Don't feel bad... ..... mine was getting about 13-15 hwy MAX when I first got it, and the power sucked. Dodge had no answers for me, and they probably won't have any for you. Mine is a 99; after I got the reflash, my mpg went way up... ... . and the power increase was noticeable. After putting the VA box on, the mpg went up to as high as 22-23 hwy (hot summer day, no headwind, doing 60-65), but averages 21 or so. City/hwy combined driving even on winterized fuel (as I type this) its getting 18. 5. (Yes kids, I AM really checking my mileage vs. gallons at fill up and YES, I am taking into account the tall tires, and NO I'm not driving like a bluehair, nor am I driving like Jeff Gordon).



The guys on this site are usually right about this one: check your intercooler hoseclamps for starters, go buy diesel from a different place for the next tank (and ask if it is WINTERIZED diesel), then go hook it to a heavy trailer and go pull the crap out of the truck on a long trip..... that seems to be a common thing many of us have done that seems to help. You'll find after anywhere from 10,000-15,000 miles the mpg and the performance will most likely increase. If not, stick one of the performance boxes on it... ... . BD Plug n Play (also known as the VA), the EZ, etc. . (sorry BOMBers if I'm leaving something out, haven't followed boxes for awhile). The box did the trick for me... ..... made the difference between keeping the rig and dumping it!



Regards,



A flu ridden Rogue Ram

:{

 

[jhenderson]

I'm clueless, what's a "reflash"?????

 

[D White]

jhenderson,

Your mpg's are about what I am seeing right now with winter fuel and cold weather. I get about 3 mpg better when warm weather gets here, and back to summer blend. Not knowing your location or what you have for a truck (2500 or 3500), I've noticed our 2500's get a little better fuel milage than our 3500's do. Our 2500's average about 16 in the winter and 19 summer. All the others except the one in my Sig. are 5 and 6 speeds, all with 4. 10's. Get your signature and location up so we can see what you have. Like others have said, should get better with time.



Doug

 

[D White]

In a reflash they re-program your trucks computer. Lot's of things can be changed with a reflash ( timing, fueling), just to mention a couple.



Hope this helps,

Doug

 

[GGates]

I get 21-23 on trips empty. I tow about 10,000 lbs and get 10-12. 5. this is driving 65-70 mph. Driving back and forth to work I get 16-17. 22000 miles on my truck. I am very pleased because with my 5. 9 gasser was getting 6-8 towing. this was cranking 4400rpm up the hills. The good ole diesel is turning less than 1/2 that.

 

[jhenderson]

I'm still not clear about a "reflash". Who performs it? and do they need my truck to do it or can I do it at home? I notice that my mileage is greatly reduced even if my dump trailer is empty and only weighing approx. 2500 lbs. . If I keep an eye on the instantaneous mileage read-out I can get 18-19 mpg on flat ground, but the minute I hit even a slight incline I can watch the mileage drop off to between 9-12 mpg. This is at 50 mph and approx. 1600 rpm. I checked all the intake hose connections and they seem tight, I'm thinking about going directly to Cummins and have them check the truck.

 

[Posm]

My truck gined MPG until the 35K mark, and yes I did use it for towing heavy loads. i can see a lot a of variation from tank to tank, I burn 2 or 3 tanks a week, by the way I drive and the speeds I run. I loose 4 MPG from 68 to 75 MPH.



You gained 100HP from your old rig. Make sure you are not exersizing all of them!!

 

[chuck3]

You have to take it in to the dealer for the reflash. This might or might not help if they do it.

 

[RThompson]

With only 5,000 miles on the odometer we towed 7,000 lb 5er across Texas in Dec. and got 2 fillups that were slightly over 14 MPG. Most of the time speeds were in the 67-70 MPH range. Empty, with mixed driving the mileage is 18-22 MPG.

Tall gear ratio and low profile 5er I believe helps a lot.

 

[RonaldLarson]

Your mileage

Is pretty normal, considering that you are apparently not any where near broken in, and have 4. 10's. Is your fuel winterized? That alone accounts for lower mileage. These engines are very close toleranced, and take a long time to seat in. Are you using a fuel conditioner? That will lube the injector pump and give you a small mileage gain. I use Red Line and Power Service.

My '99 Quad Cab averaged 20. 7 at 70MPH on a trip to Reno, Sacramento, Salt Lake and back last July, with a bed topper and weighing 7660 pounds. Your's will improve constantly with time.

I would highly recomend an Amsoil air filter.

Ron

 

[Rogue Ram]

Uh oh.........

... ..... jhenderson, out of curiosity, are you strictly going by what the computer says for your MPG??? If you have it set to do the instantaneous readout, that will certainly make you nervous... ... . on grades it'll show low mpg, on flat n level, it'll show great mpg.



Ignore what the computer shows. Go by your mileage and by the exact amount of fuel it takes for a couple of fill-ups. That will tell you whether or not you have issues. Like the others have asked, what rig do you have? If this is a 3500, you aren't that far off from what you might expect with winterized diesel. It's not time to panic just yet... ... ... give it some time.



R

 

[Alan Reagan]

I have 4. 10s and consistently get 21. 5 empty, 14 towing 10 grand. One thing besides intercooler clamps I did that has really helped my mileage and others that I've done it for is tightening the intake cover to the specified torque. Several of my bolts took two turns before reaching the correct point. Others were fine.



Also, change locations where you are purchasing your fuel. I have found that here in central Georgia, Phillips 66 will get me 1 to 2 more MPG. No bull. If I use BP or Flying J, it drops. Only one Flying J keeps my mileage the same as the Phillips 66 and it is just south of Savannah on Highway 17 and they sell Amoco there. Do some careful comparisons on mileage based on fuel stops and you'll begin to see a difference.



One other reminder. Don't know if you are using an Ebrake but if you are, it will pay you to remove and clean the Intake Air Temp sensor occasionally. That will affect your mileage also. I did some tests on my original sensor and determined it was faulty and replaced it. That also made a difference of about . 5 mpg.



Finally, depending on where you live, we are reaching the end of winter blend season. That's usually good for 1-2 mpg when they stop blending #1 and #2.

 

[DavidD]

Jhenderson, All good advice in previous posts. The one thing that has not been metioned is tire size. I have a 5sp and 3. 54 gears. I would suggest even towing with the six speed you could stand to go to a 285-75-16 tire. this will lower your rpms at highway speeds and it doesnt cost much in added friction. You will still have plenty of gear for the hills and you empty highway milage should improve. I still occasionally hit 19-20 at 60-65mph otherwise its 16-17 at 65-80mph. Good luck, Dave

 

[Bratton]

I have a 2002 QC,4x4, with 6sp. HO and 3. 55 gears (according to factory sticker,not 3. 54). I just had my first fill up the other day and found that I averaged 11. 65 MPG around town unloaded. In the engines defense however, the original NV5600 was defective and had to be replaced at 200 miles. This may have contributed to the poor mileage. Also as I was unloaded, I was doing a lot of max acceleration runs to aid break in. It will be interesting to see what I get with the next tank!BD

 

[LarryG]

I've got the 4WD, 4:10 and automatic. My first 5000 miles I was averaging 15. 2 mpg being conservative using the MPG minder on the overhead console. I was hoping for 18 when I decided to go with the 4:10 which was in dealers stock. (After test driving the Cummins, I could'nt wait to order - besides my minivan had died. ) I think I'm doing better now - time will tell how much improvement I see. Still love the truck even though the dealer took a week to replace the lift pump that crapped after 1450 miles.