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Discussion Starter · #1 ·
There is a thread kinda close to this but its a little different so I figured Id ask thinkin it might help him as well... I have been looking at a newer body style and was curious what you LMM guys gettin for milage? any increase or decrease with deletes and/or mods? I Have quite a long trip everyday so I would like to get as much as I can as Im sure all of us do hahaha
 

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bone stock 3500 dually 4wd crew cab long bed. i drive like a MAN, not a metro prius owner so mine might be on low side I get 13.3mpg in stop go/city commuting. then on freeway with 2 race bikes in bed (@1000lbs) and at speed of 80mph (NOT good for mpg) i get 13.7mpg


My 07.5 Dodge 2500 (with newer 6.7l engine and DPF) got over 15mpg WITH the stock DPF installed still and even with 35" tires!! i did run it with the egr unplugged (forum thing) and CEL was on, but in 14,000 miles never an issue and it got 2-3mpg better that way i tested it a hundred times...

Plus IMO the dodge/cummings was WAYYYYYY faster/quicker 0-60mph/low end than my chevy. I LVOE my chevy but honestly its a PIG off idle/roll ons...horrible!!

I cant wait to delete the DPF and get some mpg and hp back!!!
 

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Discussion Starter · #3 ·
Thats what Im curious about... I was readin the old MPG thread but no one had done any upgrades like exhaust, intake, tuner, or a DPF delete to see if that helped
 

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I've heard anywhere from 2-4 mpg with the DPF delete. Nothing you do before that delete is going to help a ton. After that a good economy tune and exhaust help as well. Keep it running close to stock size tires if you care at all about mileage.
 

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Discussion Starter · #5 ·
I've heard anywhere from 2-4 mpg with the DPF delete. Nothing you do before that delete is going to help a ton. After that a good economy tune and exhaust help as well. Keep it running close to stock size tires if you care at all about mileage.
Thats what Ive heard to but havent gotten a lot of confermation on that... ya I planned on stayin stock possibly lowering a little but Im not sure
 

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Just use the torsion bars to lower the front end if that's what look you're going for. If not go with some lowering shackles somewhere down the road.
I don't have an LMM and all my buddies MPG numbers are complete BS from their LMM's. No way they average 19 with just a tuner.
 

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my 08 LMM before the 6" lift and 35's was getting about 18 around town nd 23 on the highway. The mods were DPF delete and exhaust. Now with the lift and tires I get around 14-14.6 around town and anywhere from 16-17.5 hwy depending on how fast I drive.
 

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I still have the same mileage even after doing the mods in my sig. I noticed that the guys getting better mileage are the ones that live at higher altitudes or warmer climate. Just wonder if that has something to do with it. I still get a solid 15mpg no matter how i drive or what tune i'm running.
 

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Slave to the Interwebs
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I got a solid 2 mpg increase loosing the DPF and tuning my LMM. Sometimes it is closer to 4mpg if I keep it around or under 70 but that is just to hard for me. In town it is a Pig but it weighs about 4k more than a stock truck. I tuned a 08 LMM and he went from getting 15 on the highway to 19 running 75-80mph.It is a CCSB and 4wd. My 3500 dually LMM gets 10 in town and 12-14 on the highway it is a CC with a utility box and pipe rack on it.
 

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I'm averaging 15.3 mixed city/highway with my only mod being larger than stock tires. I will be installing a quad s2 and mbrp 4" exhaust this weekend to delete the cat, dpf and muffler. Soon I'll know how much my fuel economy has increased once I have logged a few miles after the changes.
 

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The Good Son!
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The Tale of two LMM's!!!
I got rid of the 2008 because I wrecked it and the repairs weren't done properly.

 

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I am getting 13 mpg around town and around 16 mpg on the highway if I drive like I have some sense, most of my highway has been loaded and the city is unloaded.

I will update after the Banks CAI, 5" turbo back MBRP Exhaust and EFI Live install I have in the works.
 

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2008 LMM cc/sb 4whl 3.73 all stock 11 hour drive home from purchase I checked DIC speed vs mpg.

75 low 17
65 18.5
55 19.5

hand calculated 75% city 25% highway 16.5 mpg. I drive it easy, I keep it under 2k 95% of the time. Only the occasional romp.

Removed exhaust, put on diamond eye d/p, 5inch mbrp straight exhaust and Quadzilla S2 Econo tune.

Maybe just over 1mpg improvement from stock, says the DIC. I say as B/A as it sounds I at least gained 5mpg hahaha!! However I don't get the 10-12mpg during regen anymore....

Now put on 20 x 9 kmc monsters, 33 in terra grapplers, crank the bars some and have lost almost 2mpg doing so. Don't know if lifting the front had anything to do with it but I am sure adding wheels & tires that weigh probably over double what I took off had quite a bit to do with it. Hoping to get some back with EFI when I get it.

Of course I did not buy the truck for mpg but this thing gets about the same as my 1/2 ton silverado 2wd did unloaded while much better mileage pulling my trailer.
 
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