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Improve LMM fuel mileage

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99K views 69 replies 26 participants last post by  407driver  
#1 ·
My friend has a 2010 LMM that averages 8-10 mpg. What does he need to do to get better economy? He talked to a local diesel shop and they told him about deleting his DPF and tuning it. Lol they tried to tell him that Bully Dog was the best programmer :rofl So besides a DPF delete and tuning (I told him about EFI Live) is there anything else to he can do?
 
#6 ·
DPF delete and EFI LIVE

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#7 ·
Efi from longhorn fab shop


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#12 ·
More oxygen in the cylinder for a more complete burn.
 
#13 ·
I also jut bought a LMM and it is horrible on fuel,I get about 400km to a tank,already has DPF delete also,Im not sure what to do?
 
#14 ·
Mines exact same 400 Everytank


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#15 ·
what about in the summer without winter fuel? Im ordering a lift for this thing this week and now im scared shitless how much worse its going to be on fuel
 
#16 ·
I'm not sure I got mine in September but seemed tk get the same. I'm in the same boat I'm ordering a lift on the next few weeks as well. It seems like it was better on fuel without the delete


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#17 ·
I ordered my lift and rims today ha,so we will see how much worse it gets! I was wondering if mine was better on fuel with the dpf on,but who knows
 
#18 ·
Where'd you order from ? I was told national 4wd In Burlington is good.


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#19 ·
get that dpf off
 
#20 ·
We both have dpf deleted


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#23 ·
Ive only had my LMM for two tanks and i filled up at the same smalltown gas station twice,il switch it up this time but i guarantee that wont change it much
 
#25 ·
Hm I'm not really sure then. I've done everything that everyone says necessary to rt better mileage but it's still brutal. My buddy's lb7 gets 700 k to a tank.


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#27 ·
Doesn't really matter how I drive I've tried both and still get 400. And ya fuel filter is fresh. Reason I sold my lifted 5.3 was cause I was getting 350 to a tank. And I'm afraid this lmm won't be getting much better with a lift


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#28 ·
Not busting balls, but is that gallons used or going off the fuel gauge? There's roughly 8 gallons left on my tank when it's on empty. 26 gallon tank and it says empty at 18-19 gallons used. Common lmm deal.


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#29 ·
I run it all the way down. I'm from Canada and it takes 78 liters sometimes to fill and it's an it's basically right with what the dash says


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#30 ·
So it's a 98 litre tank ? I thought it was 80 ?


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#32 ·
Oh really ? I wasn't aware of that. That probably explains why I'm only gettin 400 k to a tank cause when I fill up it takes 75-78 litres which means I got another 20 left. I will go longer with this tank and watch the fuel used on the dic... I wonder of there's a fix for this


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#34 ·
I'm not so worried. I just thought they got a bit better mileage


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#36 ·
Winter blend has a little to do with it. But good I'm looking forward to the summer


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#41 ·
Ive only ever put like 78 liters in my tank also,cant believe theres that much fuel left with the light on
 
#42 ·
Me too ? I'm wondering if I should try and run it longer and gauge by the fuel used on the dic ? I'm just so used to filling up when I see the light on in any vehicle


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#43 ·
Its a thought,I would just really hate to run out of fuel thats for sure
 
#44 ·
Lol me too. I always thought it was a 80 litre tank lol


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#45 ·
There was a good discussion on here a while back about the fuel tank sizes.There are only 2 sizes one for sb and one for lb.If you want to figure out how far you can get just fill up when you normally do and to the mathto see how many k's on 98 L.That way you don't have to worry about running out.
 
#46 ·
Yea I would get about 500 or so wih the 98 litre


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#48 ·
Ya i dont ever want to push my truck to gas station for fuel or be the idiot on the side of the road with a Gerry can..I'll fill up when the little light tells me to...:)