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05-CR, 6 Spd std, 4x4, level kit. Colt stg 3 cam, billet turbo, 4” exh, smarty, ARP studs, 35” boots
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Oh I remember hearing the lies of 25mpg that led me to buy my truck. I'm living that 13-16mpg life.
Honestly, I’ve seen guys getting 22-25 mpg with a cummins truck. My nephew had a 2002, 4x2 with a manual trani. He was getting almost 30. I don’t know how, but it happens.
like you, I struggle to push over 17, and it frustrates the **** outta me. But then again, I can pull a small house reliably... for 500,000 miles.
maybe it’s about where we place the value
 

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Honestly, I’ve seen guys getting 22-25 mpg with a cummins truck. My nephew had a 2002, 4x2 with a manual trani. He was getting almost 30. I don’t know how, but it happens.
like you, I struggle to push over 17, and it frustrates the **** outta me. But then again, I can pull a small house reliably... for 500,000 miles.
maybe it’s about where we place the value
Yea, you can average over 20 on a long highway trip. Its not super hard as long as the wind if in your favor. I have done it plenty of times from Texas to AZ and back. But realistically if you hand calculating the trucks actual average on normal driving around between tanks, some freeway, some stop and on city streets it won't be over 20 I don't care what your doing to improve MPG. Especially if you averaging over a longer period and lots of tanks. nothing wrong with your 17 average, that's about right and realistic.

This is where people get mislead, they see one guy that only drives on the freeway bloating 22+mpg and think that's what the truck should get. No, that what the truck gets while holding 60-75mph on the highway. Toss in a dozen stops and accelerations form 0 to 70 over the consumptions of 30 gallons and you're falling off the charts well below 20 most of the time.

He was getting almost 30.
he is lying to ya or his lie-o-meter is lying to him
 

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Discussion Starter · #43 ·
@‘04CTD
I'll see what manual math shows for MPG, then maybe ill elliminate the EDGE just to see how mpg does. However, I hear its nice to use mode #2 on Edge evolution when pulling because of the change in something. Something with the trans. I do need to check boost leaks. I have to find out how to do that accurately somehow.

@steve05ram360
Ya I dont know how well the fuel is doing. For all I know, injectors could use some cleaning. I did run 1 jug of diesel kleen. Wow 23MPG, thats fantastic When you guys talk about HP TUNE, are you referring to hypertech like below? And if so, is it highly tunable? or is it just another plugNplay device? Does it come with bluetooth or some OBD connection? It may work, but the ROI on that bad boy is not going to find its way into my pocket for years lol. Which low cost device do you suggest for custom tuning?

931391



931390
 

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Yea, you can average over 20 on a long highway trip. Its not super hard as long as the wind if in your favor. I have done it plenty of times from Texas to AZ and back. But realistically if you hand calculating the trucks actual average on normal driving around between tanks, some freeway, some stop and on city streets it won't be over 20 I don't care what your doing to improve MPG. Especially if you averaging over a longer period and lots of tanks. nothing wrong with your 17 average, that's about right and realistic.

This is where people get mislead, they see one guy that only drives on the freeway bloating 22+mpg and think that's what the truck should get. No, that what the truck gets while holding 60-75mph on the highway. Toss in a dozen stops and accelerations form 0 to 70 over the consumptions of 30 gallons and you're falling off the charts well below 20 most of the time.


he is lying to ya or his lie-o-meter is lying to him
A while back after the bet was over (bet was in 2018 & with co-worker that I could not get 5 tanks to average 23.0 or better), I tracked mpg numbers in a spreadsheet for just over a year, the average was right at 20.9x mpg (iirc). During that year I did a lot of volunteer work rehabbing/building trails in the back country. 90~95% of those include off road miles up dirt roads, several were in the 16~20 mile range 1 way (same job site) with a 3000+ ft climb. I can go grab all the receipts again for the last year to see where I'm at now... I can say though that DGAS tanks are easily over 20.

And yes, my truck is far from stock, here are the key changes (wont list them all but the ones that helped get me up into the 20~21 mpg range.

Aluminum Engine pulleys, noticeably reduced engine load & improved throttle response. Used HPT to leverage that change for improved performance (cant say it changed mpg's)

Aluminum Driveshaft, same effect as the pulleys, however truck LOST boost after the install, this had me scratching my head for a bit until I realized the throttle response change was blowing past the cells in the tune that were helping get the turbo spooled up, fixed the tune and whola.

2010-2011 Ram Alloy wheels, improved throttle response with lighter steering feel.

2nd air dam mounted under the swaybar... measurable difference on 3 back to back runs I did after attempting a failed V2 of the air dam. V1 proved to be the better of the designs over none, and V2 really sucked. Just last week I realized there was an issue with the V1 design that I never caught up until now. Air was spilling over onto the wheel area on one side but not the other. That was increasing drag. Fixed it last Friday and am running a full tank (fill up today) to compare against.

Bed seals (vertical ones)... back in 2018 when I first tired them, did the install after picking them up and the truck felt "heavy"... hit a down grade on the way home that is fairly long & steep, usually accellerate pretty good on it. That was not the case after the install... truck held its speed all the way down the hill. Another head scratcher. Figured air was flowing into the rear bumper so as an experiment, I taped the openings up. The change was night & day, I was then able to go into neutral on "flatter" down grades w/o loosing speed, maybe -1~-1.5 according to Torque & the GPS. Recently went back to them to try and solve the bumper issue and realized I dont have to have them extend all the way down, so I trimmed them to the body line that extends the length of the truck and into the bumper. Seems to perform even better than it did with the tape over the bumper opening however I dont have back to back configurations to compare against. I figure the airflow that is going down the side of the truck is also hitting the rear tire more as well as flowing into the bumper.

The horizontal one... this one actually caused more down force on the rear of the truck which increased drag. Increased drag = lower mpg's. If I remove it I go back to where I was and should see a slight increase in mpg again. But as of now, getting 23.0~23.3 mpg's, cant complain.


Post #1 shows where I was before the makeover...

The aero mods thread...


Most owners wont go to the lengths that I did to improve mpg's, they will sell their truck before its worn out. For me, my truck is there till the end... I love it and now it doesnt cost me an arm & a leg to drive it. There have been a few that have tried some of the mods and saw improvements, but I dont think anyone has all the way. It would be awesome to hear that someone is all in and would reply with changes in mpg's.

My trucks not magical, it took a lot of testing of different things to get it where it is today. Once upon a time (with the AT) it was in the 12~13 mpg range... on the hiway!

Yes, it can be done.


edit: whoops, forgot to add that I'll be happy to post up numbers after the road trip Saturday (race day... karts). 100% DGAS tank.
 

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@‘04CTD
I'll see what manual math shows for MPG, then maybe ill elliminate the EDGE just to see how mpg does. However, I hear its nice to use mode #2 on Edge evolution when pulling because of the change in something. Something with the trans. I do need to check boost leaks. I have to find out how to do that accurately somehow.

@steve05ram360
Ya I dont know how well the fuel is doing. For all I know, injectors could use some cleaning. I did run 1 jug of diesel kleen. Wow 23MPG, thats fantastic When you guys talk about HP TUNE, are you referring to hypertech like below? And if so, is it highly tunable? or is it just another plugNplay device? Does it come with bluetooth or some OBD connection? It may work, but the ROI on that bad boy is not going to find its way into my pocket for years lol. Which low cost device do you suggest for custom tuning?

View attachment 931391


View attachment 931390

Wow... mine ran me $600 IIRC with endless tunes (my tunes)
 

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05-CR, 6 Spd std, 4x4, level kit. Colt stg 3 cam, billet turbo, 4” exh, smarty, ARP studs, 35” boots
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Yea, you can average over 20 on a long highway trip. Its not super hard as long as the wind if in your favor. I have done it plenty of times from Texas to AZ and back. But realistically if you hand calculating the trucks actual average on normal driving around between tanks, some freeway, some stop and on city streets it won't be over 20 I don't care what your doing to improve MPG. Especially if you averaging over a longer period and lots of tanks. nothing wrong with your 17 average, that's about right and realistic.

This is where people get mislead, they see one guy that only drives on the freeway bloating 22+mpg and think that's what the truck should get. No, that what the truck gets while holding 60-75mph on the highway. Toss in a dozen stops and accelerations form 0 to 70 over the consumptions of 30 gallons and you're falling off the charts well below 20 most of the time.


he is lying to ya or his lie-o-meter is lying to him
I didn’t believe it either, but I did the math myself. We took a road trip together. 29.6.
I have no reason to BS on here. I don’t have anything to gain by it
 

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A while back after the bet was over ....
yea bud, your are a bit of a special case here. Just make sure your not leading people to Cummins because of the amazing milage... not telling them all the effort you have put in. In all of my statements above, you don't count :p

I didn’t believe it either, but I did the math myself. We took a road trip together. 29.6.
I have no reason to BS on here. I don’t have anything to gain by it
29.6... something is off.. look at all the work @steve05ram360 is putting in and not getting that. I realize you don't have any thing to gain but 29.6 is basically unbelievable. I don't buy it.
 

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yea bud, your are a bit of a special case here. Just make sure your not leading people to Cummins because of the amazing milage... not telling them all the effort you have put in. In all of my statements above, you don't count :p


29.6... something is off.. look at all the work @steve05ram360 is putting in and not getting that. I realize you don't have any thing to gain but 29.6 is basically unbelievable. I don't buy it.
I specifically remember stating that “I have nothing to gain”
And I don’t. I’m not selling snake oil to help you get there....
I’ve never seen it in another truck... but I did see it with my own eyes, and I did my own math.
I’m not really surprised that you “don’t buy it”
I didn’t either, to be honest.
He said it is just the “normal” for that truck....
I want to dissect it !!!!!
 

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Filled up, right at 23.0xx mpgs... I'm going the wrong way with the tune. Going to dump the 23.6x tune back in and run it

FWIW, the outgoing tune that got me the 23.0 was a 2 event tune. The area that used the Post event was there to help spoolup. Did not think it would have a negative effect on mpg's (was expecting minimally 23.3 again... that was the previous tank before the 2 event tune).

2 things I want to re-examine is the horizontal bed seal, what effect will extending it to the sides of the bed cause? And... removing it to feel what it is like again without it (it did ad stability to the rear). I also want to start experimenting with closing up the underside of the bed to reduce the aero eddies that occur up there. I know they will create drag (the eddies) but dont know if reducing them that high up will have any effect, good or bad.

So I got curious, tallied up all the fuel receipts from late april and on (rest is somewhere in the house)... results below... the short fill tanks are either a failed experiment or 100% DGAS tanks.

Not bad, 22.3 mpg over nearly 8k miles...there is a clear jump in mpg after the vertical bed seal install plus the higher rail pressure tune. I just dont know which caused the jump or which was responsible for what % of the jump. During the months of May & early June, 6~7 work parties were in those results. thinking about it, 3 were drive & park, all paved and 3~4 were on dirt.


931411
 

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Ok I’ll show my ignorance. What’s DGAS?
 

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:ROFLMAO:

Its too early for this. Yall got to calm down.

Steve, the vertical bed thingy, its in your aero thread? I'm curious.
 
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:ROFLMAO:

Its too early for this. Yall got to calm down.

Steve, the vertical bed thingy, its in your aero thread? I'm curious.
yup, it is.. mid 2018 in that thread for the first use of them with the bumper taped up. but... to cut to the chase, cut them so they cover from the top of the bed to the recessed body line. there are pics in that thread that detail it.

the horizontal seal, it proved to drop mileage with the tonneau cover open, and a tad bit with it closed. it did appear to create more downforce which added stability to the truck

 
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yup, it is.. mid 2018 in that thread for the first use of them with the bumper taped up. but... to cut to the chase, cut them so they cover from the top of the bed to the recessed body line. there are pics in that thread that detail it.

the horizontal seal, it proved to drop mileage with the tonneau cover open, and a tad bit with it closed. it did appear to create more downforce which added stability to the truck

ok Steve, so toneau closed for better fuel mileage, horizontal seal between the box and cab, as you described ...
I’m running a smarty touch, and it doesn’t seem to matter where I set it, I can’t catch a break on my mileage getting above about 17.
min looking at some skinnier and less chunky tires. I’m certain that’ll help a bit too.

my biggest curiosity is: what RPM have you found is the “sweet spot” for fuel mileage in these engines ?
 

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You say you don't care and its impossible. I say you want a dead community with no returning longterm members to this toxic mess that CF has become. Im about to go inactive for a few more years til these old timers forget how to use computers. Toxic. Toxic. I dont need ANYTHING from this forum anymore. I come here to help Cummins enthusiasts. You know... people who actually turn bolts on their trucks, not just their jaws.

We should ban all MPG threads then, if we're all lying anyways. Let alone hand calculating 1 in 3 tanks of fuel on all my trucks since I started driving. Not the evic. Hand calculating, with topping off, with enough to know an exact average.
hey now, what you so mad about? toxic what now? I looked through posts and didn't see anything toxic... just people talking. I guess I was likely the worse one and I don't see anything "toxic". Maybe "confrontational" at best because I flat out do not believe a guy's buddy was averaging 29+mpg, hand calculated tank after tank... It's funny because all the trucks you posted with MPG numbers are about in line with what I think most consider totally achievable for a normal truck/driver with good habits and better driving conditions.

and btw, that's ok to disagree, debate, state your opinion. We don't have to agree or believe everything we see or hear, we can still be friends. We don't melt like a snowflakes here. Good luck waiting out the old timers, most of them are not that old :D


btw, that Blue 04.5 SCLB is freaking sweet..
 

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hey now, what you so mad about? toxic what now? I looked through posts and didn't see anything toxic... just people talking. I guess I was likely the worse one and I don't see anything "toxic". Maybe "confrontational" at best because I flat out do not believe a guy's buddy was averaging 29+mpg, hand calculated tank after tank... It's funny because all the trucks you posted with MPG numbers are about in line with what I think most consider totally achievable for a normal truck/driver with good habits and better driving conditions.

and btw, that's ok to disagree, debate, state your opinion. We don't have to agree or believe everything we see or hear, we can still be friends. We don't melt like a snowflakes here. Good luck waiting out the old timers, most of them are not that old :D


btw, that Blue 04.5 SCLB is freaking sweet..
I never took it as confrontational.....
we are grown ups on here, we are allowed to have our own opinions and not feel crucified.
Im here to learn, and contribute where my experience allows it. That’s about it.
But thanks for coming out !!
 
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Lol... these MPG threads all end up the same...

Btw, everyone on this forum gets better fuel economy than me! :)
 

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My stock 03 4x4 auto dually with 4.10's gets around 14 mpg solo unless its all highway. My 95 2wd dually gets a little better. When the 95 dually was bone stock it would get 23 mpg on the highway and around 14 mpg towing my 9K travel trailer. But 160 hp was not enough!
 

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ok Steve, so toneau closed for better fuel mileage, horizontal seal between the box and cab, as you described ...
I’m running a smarty touch, and it doesn’t seem to matter where I set it, I can’t catch a break on my mileage getting above about 17.
min looking at some skinnier and less chunky tires. I’m certain that’ll help a bit too.

my biggest curiosity is: what RPM have you found is the “sweet spot” for fuel mileage in these engines ?
You will need to test the horizontal seal's performance on your truck, I have a tailgate spoiler installed and the airflow off the cab has a place to land. Not sure how that seal will perform on a truck without one.

I dont have a specific RPM number to give you, it is tune dependent. For mine, its between 1800 & 2000 rpms is where my truck lives most of its days. For the best mpg's everything else aside, you want the LPP between (iirc) 12-16* ATDC. You cant measure it, the only way to figure it out is to be tuning your truck yourself. On mine, I look for the haze @ a steady state and dial timing back 0.25* and it puts me in that sweet spot. LPP = Location of Peak Pressure, and is talked about in the article that is linked in the HP Tuners Lessons Learned thread.

If you dont tow and can tolerate a 200*f stat, it is good for approx 0.6~0.8 mpg on a stock tune (from what I found back in the cold weather thread).
 

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Lol... these MPG threads all end up the same...

Btw, everyone on this forum gets better fuel economy than me! :)
While that is true, the audience changes over time. The way I look at it is if it helps people great, maybe the thinking that comes from these threads may transfer over to people that they are in contact with which might make them think more...

Have you tried anything to improve mpg's? Minimally, those vertical bed seals, stock air box and a 200*f stat should definitely show up at the pump.
 
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