Add on's for improved fuel economy

[243]

My weekly mileage hovered between 17. 8-18. 5 before the dealer re-flashed the PCM for the low power TSB in April of 2000. I can't remember what the TSB number was but the motor was much quieter and pulled better, however, the mileage dropped to 16. 8-17. 5.



I drove a little over a 100 miles at 55 mph and it gave me 23. 8 mpg. I realize that 100 miles is not the same as a full tank but I believe it represents what you can expect by slowing down.



I believe I sold my 99 with 82K miles and the average mileage was 17. 6.

BTW, it was QC 4X4 short bed 5spd with 3. 54's and 285/75/16 MT's.

 

[PHaller]

I found that what helped my milage the most was breaking in that Cummins motor. Pull a 15,000 lb trailer 10,000 miles up long grades and you will see a major difference.

On my 97 12 valver from the showroom floor in California to Denver the best I could do was about 16 mpg. Hooked up a trailer in Denver and drove back to Ca. After that, I got 19 mpg. Then, I bought a 15,000 lb. 5er and dragged it all over. Now I can achieve 22mpg on a freeway, solo, going 65. If I go 75... I get 18MPG.

-Paul R. Haller-

 

[drees1]

One thing not mentioned is to add more overdrive to the gearing, especially 4. 10 gearing. Cruising at 1500 - 1750 helps a lot. the lower, the better, as long as the engine will pull it and some boost is available if needed. I'm sure I would not get 21. 5 mpg consistantly at 65mph in a 3500 dually with 4. 10 gears if I did not have the gearvendors OD. Gearvendors in OD with 4. 10 would be the same as a stock truck with 3. 3 rear gears in 5th. My small 215 tires don't help as far as "gearing" but they are narrow.



Also, my tall fiberglass "Swiss" topper seems to add 1/4 to 1/2 mpg when it is on. I record all fuel fills since owning truck.



Doug Rees

 

[SmokinJoe]

Re: Sometimes your just stuck

Originally posted by LoneRam

Since I drove off the lot new until now my mileage has NOT changed from 15 +/- . 5.

Re-Touque your head bolts

 

[DBVZ]

From what I read here it still looks like Lone Ram has a problem. Am I wrong? I have been told these engines "learn" how you drive, and take a set from the first 500 miles. True? And that you can start over by disconnecting the battery for a few minutes, and driving differently. True?

 

[Gordon Maney]

Modifications to increase fuel economy

There are lots of threads on this forum about how to increase power. I have the 2001 HO with 6 speed. I am interested to know if there are things I could do to get metter fuel mileage. What are your thoughts on this?



thank you...

 

[mikel]

Hey,



From what I have seen the biggest thing to do to increase mileage is slow down. I'll get 23-24 mpg at 65 about 20 at 70, and in the teens faster than 70. Not trying to keep up with the leadfoot beside you from traffic light to trafic light will help as much or more than slowing down on the road.



I have also seen 275's help mileage a little. I think these engines run better (more efficiently) with 275's than the stock injectors.



Some people I know say that they get better mileage with the VA or EZ, but I've never tracked the mileage change any of these boxes make myself, so the best I can give you is hear-say on that.



DDII's *will* cut into your mileage, but you trade mileage for



I have calculated mileage by hand for every tank over the life of the truck, so as far as my truck goes I can tell you a few things from solid data.



Some say mpg goes up as you get 10k or 20k on the truck. I have not seen this. My truck got the same mileage from day one.



Others say that pulling heavy will help the engine seat-in and make better mileage. I pulled heavy with 1200 miles on the truck, so I don't have too many miles of refrence before the heavy pull but I didn't see a mileage increase after the heavy pull.



Other than these things you can run your tires at the max pressure for less rolling resistance, get a bed (toneau?) cover to help with airflow over the truck, and leave anything at home that you don't need in order to reduce the weight of your truck as much as possible.



That's about all I can think of right now, hope it helps!



Mike

 

[CFAR]

21 MPG before and after mods, but at < 65 mph on the freeway, and <1800 rpm shifting, on flat ground of course with no load.



Slow and steady acceleration.



Woody

 

[CFAR]

21 MPG before and after mods, but at < 65 mph on the freeway, and <1800 rpm shifting, on flat ground of course with no load.



Slow and steady acceleration.



Right foot in the grill (all the time) ==18-20mpg



Mileage kept since new,



Woody

 

[illflem]

Since this applies to all generations

Moving this where more folks can see it and merging it with a similar thread that was in 24 valve

 

[Bill Lins]

Originally posted by Deezul 1

How about them magnet thingys on the fuel lines and the little propellers in the air intake for a "Vortex" effect for better combustion. :--)

Don't forget the TurboGator thingamabob for your exhaust!

 

[illflem]

The TurboGator is also excellent for sliceing up spuds for fries

 

[Rogue Ram]

Mine was a PIG when it was new...

And was getting 11-13 mpg on the HIGHWAY at 55 mph! "Way back when" this was the old CDW website I got flamed (under the old handle) for reporting this. The dealer refused to deal with the issue, blamed my 285 series tires for it all, and sent me on my way. DC eventually got the clown to agree to having it dyno'd... ... . my stock rig ended up with 205 hp--can't recall the RPM at the moment. DC and the dealer told me to shut up and be happy. Pulling a trailer was a JOKE... ... on small little hills with a 3k travel trailer I was having to shift into 3rd just to maintain 55mph!



I ended up putting miles on it... ... . and continued towing for a few trips even though it drove me nuts. Then, TSB 18-11-99 came out... ... ... got it reflashed, and as it broke in, it was like a different rig altogether. The MPG came up to 18-19 on the hwy at about 65 (factoring in the tires).



Finally, some miscreants on this site convinced me to get a box... and once the VA was on, woo hooooo!! My MPG went on up to average 20. 5 city/hwy driving, and when I'm on the open freeway (hotter weather seems to help, don't ask me why) and keeping it at 2000 RPMs or so I have gotten upwards of 22. 5 to 23 mpg. Yes, mine is a 4x4 with the 4:10 rear end.



I have since added the AFE Mega Cannon, along with Jardine's 4" exhaust (turbo back)... ..... and this has made no diff in the MPG whatsoever.



Take the box off, MPG drops instantly. Put it on, goes right back up. For me, its made the diff between dumping it and keeping it.



My . 02 worth... ... .



Regards to all,



Rogue

 

[barbwire]

mileage

Illflem; can I buy your truck?

It doesn't seem to matter with mine, if I travel 65mph, or 75mph, or pulling a load, or running empty. I GET approx. "10. 5"mpg I don't believe in driving like a rabbit either. I've had it to 2 different dealers, and had it put on the computers 3 times. No luck! I do like to run on cruise control, but the difference between what I make and all that I have read about, cannot be just my driving habits!!! There is no way that it can make anywhere from 5 to18 mpg difference . I would guarentee that anyone that claims to be making 20 or so, could not get into my rig and improve the mileage by more than . 5 to 1mpg. there is just no way. I cannot complain about the power, though. It seems to sense the need for more, when I hook up to something heavy, and walks away with it.

 

[Rogue Ram]

Barb, something is seriously wrong with your rig to only get that MPG. One problem is that you have a one ton... ... they do seem to be a little worse than the 3/4 tonners, but not that much.



I wonder what a Cummins shop, or a diesel performance shop could do for you? Someone else may chime in here, but wouldn't the INSITE program answer the question on this one????



How many miles is on your rig????



R

 

[illflem]

I agree, something is wrong. The 4. 10 gears aren't helping either

 

[barbwire]

mileage

Rogue Ram; I currently have 60,000 miles on the rig. I am constantly leaving my money at one fuel station or another. And the irony of the whole situation is that I bought the Dodge w/Cummins, because I have heard time &time again about the economy of them. Beings it keeps my pocket book drained of any extra funds, I fear that I may be throwing good money after bad. It's scary. But upon your suggestion, I will stop in at a Cummins dealer when I get a chance. Thanx for the comeback.

Illflem. I know 4. 10s are part of the culprit. If I could afford to do it all over , I would trade for something with higher ratio.

Thanks again fellows

 

[jkern]

here is my story for what it is worth...

i too have been plagued with fuel milage problems since my truck was new, and i realize i have not helped it with my mods, but here is my story and opinions. when my truck was new and stock i got about 16. 5 average out of it. then i got a bumper with winch, 33 inch tires and a fueling box... all of which has dramatically reduced my MPG. i have calculated and corrected for my tire size when reporting numbers. i have check it with a calculater and a GPS unit and get virtually the same numbers. anyhow i get frustrated with this topic because i see guys with great numbers with the same mods that i have and wonder how... but one thing that i didn't see many people mention is the TYPE OF TERRIAN on which you drive. the hills and mountians of western PA kill milage, however the flat lands are great for MPG. so i get 14. 5 mpg empty, loaded, on the highway and on the secondary roads... only when i tow my trailer (3500-10000 lbs) do i ever notice a decrease and then it goes to about 13mpg.



so back to the topic at hand... what mods help??? not many, mostly just the timing boxes, think about it, if you are adding fuel your not gonna gain miliage. the box i have claims 1-2MPG gain... let me tell ya it doesn't do timing and i get 1-2 MPG LESS with it on. oh, well... that is the price we pay for fun i guess.



hopefully i didn't ramble too much... i agree 100% with HC's long post... but don't forget to add in the type of terrian that you drive on... it makes a significant difference.



Jeremy

 

[tazzen]

barbwire





hey i got the same set up as yoiu do. look at my sig.



but i got the quad cab. and my rig weights in at 9000 lbs. on a daily bases with my tools.



i averg. 15 city . and 19. 6 highway. all hand figuring.



i have 20,000 miles on her now. been getting this mpg from mile one.



4:10s aint killing you that bad.



i would say yours has a problem.



ed

 

[RAndrae]

fuel mileage

I have an 02 4x4 quad cab LB 3:54 gears and auto with 11000 mi. I drove it normal and changed the engine oil at 1500 Mi and every 3000+ - since. I also changes the diff oils at 6000 when I put hytecs on. I live at 2200 foot elevation mild terrrain (foot hills) I also put 4" exaust and in box K&N.

Since new I have seen a slight increase in mileage I do not know if they are due to the Mods or not but I consistently see 14. 5 MPG and about 15. 5 going to the valley. I am not happy nor impressed ALSO not to ask a dumb one but what does TSB stand for. Any ideas out there ???? HOw does one check/ change timing Is 16 good like I saw someone posted??