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Discussion Starter #1
Ran through my first tank and got 18.2 mpg. 90% of my driving is highway (with the cruise)and about half the highway I [email protected] 75mph. What's the sweet spot for mileage on these rigs.
Also what is everyone else *really* getting.
I'd like to see her at 20. I'll be getting a programmer soon and I figure that should help.
 

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I filled up last week and mine was getting just over 18. That was back and forth to work which consists of highway/city driving for me. I've found that my mileage decreases the further over 65 I go. It's tough to keep it 65 or under though on the freeway! haha.
 

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1800 rpm is the sweet spot.
 

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Oh...... Squirrel!
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I got 16.5 mpg with some highway and alot of back roads driving, but Im still on my second tank, but Ive done alot of highway driving this time so we will see
 

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i hit 21 with my 245/75/16
and i hit it once on my 285/65/18 there the same hight just a wider tire.
its a 32.8
 

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I went up north this weekend and hit 21 mpg with 265 and 168k on the clock. I was pretty happy.
 

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Thought I'd update...cause I'm impressed with this: filled up today...back and forth to work driving (30 min each way, mostly stop and go) and hand calculated....19.48!! Damn! I've been trying to keep it under 2 grand and below 5 psi. Seemed to work well. :D
 

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The Good Son!
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You found the magic formula... under 2K rpms and low boost!!! All I will add is to keep the tire size close to stock, and use quality fuel with a quality additive.

You’d be amazed at what these truck are capable if you go easy on the skinny pedal.

I have seen 21mpg with a crew cab, 4x4, dually staying under 70 mph (68 mph to be exact) and using those techniques on the highway.
 

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Yeah, I know you're right. Easy to say...tough for me to do! haha
 

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Discussion Starter #11
Two tanks ago got 19.1. Last tank was my first tank with the Stealth2 on 90HP setting. Even enjoying the extra hp and dusting a few fbodies, got 18.1. I thinking 20+ should be easy.
 

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I just picked up my LMM and I am getting 19.6 MPG stock with a heavy foot. A whole lot better than 13.5 my gasser was getting. All hand calculated of course.
 

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I just picked up my LMM and I am getting 19.6 MPG stock with a heavy foot.
If it's stock...have you went through a regen? That sounds awfully high with a DPF LMM.
 

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The Good Son!
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If it's stock...have you went through a regen? That sounds awfully high with a DPF LMM.
Maybe, maybe not!

I can get over 18 mpg with the truck in my signature with a somewhat light foot and DPF/CAT intact.
 

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my truck the best tank i have seen with the mods in my sig without the programmer was 20.4 going 65 i went 495 miles on the tank. been driving to work speeds between 45 and 61mph i got 17.38 on the 120hp tune. currently on 65hp tune and will see if i improve
 
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